RAID 5 - hardware vs software questions

Hi all,
Im thinking about building a RAID 5 server. Right now I have a Thecus 1U4500 (4x500GB RAID5) and I really like it but have outgrown it. And really I would rather build my own just for the fun of it.
I would like 8-12 drives, and RAID 5 or 6.
Here come the questions...
The Thecus server is software RAID 5, I think 1.XX GHz celeron and 512MB RAM. It has decent performance (at least for what I use it for).
So hardware RAID, expensive for 8-12 drives of RAID 5 or 6. Although it seems like it would be pretty easy to set up as long as there are appropriate Linux drivers. If I went with hardware RAID, how easy is it to expand the volume? I would have to use LVM to make this possible correct?
Software RAID, I have read up a little on EVMS. I am a little confused about it though. Does EVMS just use plugins for its functions? Does it use some other system to control a RAID volume?
I think I would run the OS (Arch) on a dedicated drive, perhaps a small flash disk or something, then just have my data on the RAID volume. If I do it this way, and I corrupt my OS somehow, will I be able to reinstall the OS and get my RAID functioning again? There is no software RAID that supports RAID 6 is there? Can hot spare be supported in RAID 5 on software?
At the moment I am leaning towards software RAID... if nothing else just to see if I can do it. But you guys with experience, how much processing power would I be looking at needing for 8-12 drives? Or is that many just out of the question with software?
Thanks!!

Unless you get some very expensive hardware raid, use software. I don't need to say any more Jeff Garzik sums it up perfectly in this message and the included links. I know little about raid, but not many know more than Jeff about using it under linux.
http://www.ussg.iu.edu/hypermail/linux/ … /2811.html
James
Last edited by iphitus (2007-07-20 08:50:29)

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Help thinking buying a W530 with RAID hardware or software

I'm thinking to buy a W530 with RAID. I have no experience with RAID and never thought that RAID is possible in a labtop.
I have read that RAID comes in types of implementation, software or with a hardware controller. In this forum I read that in the W530 service manual the RAID controller has been disappeared from the motherboard (I have not checked by myself).
Does anyone know if RAID is still implemented by a hardware and not by software.
Frank

From the forums and the rep I spoke with, RAID is implemented in the hardware. You will not be able to enable RAID later on if you did not order it like that from the factory.
You would probably be better off going SSD in the primary and a larger capacity HDD in the ultrabay. You'll have better speed, more reliability, and lower power consumption in general compared to 2 HDD in RAID 0.

To RAID or not to RAID, that is the question

People often ask: Should I raid my disks?
The question is simple, unfortunately the answer is not. So here I'm going to give you another guide to help you decide when a raid array is advantageous and how to go about it. Notice that this guide also applies to SSD's, with the expection of the parts about mechanical failure.
What is a RAID?
RAID is the acronym for "Redundant Array of Inexpensive Disks". The concept originated at the University of Berkely in 1987 and was intended to create large storage capacity with smaller disks without the need for very expensive and reliable disks, that were very expensive at that time, often a tenfold of smaller disks. Today prices of hard disks have fallen so much that it often is more attractive to buy a single 1 TB disk than two 500 GB disks. That is the reason that today RAID is often described as "Redundant Array of Independent Disks".
The idea behind RAID is to have a number of disks co-operate in such a way that it looks like one big disk. Note that 'Spanning' is not in any way comparable to RAID, it is just a way, like inverse partitioning, to extend the base partition to use multiple disks, without changing the method of reading and writing to that extended partition.
Why use a RAID?
Now with these lower disks prices today, why would a video editor consider a raid array? There are two reasons:
1. Redundancy (or security)
2. Performance
Notice that it can be a combination of both reasons, it is not an 'either/or' reason.
Does a video editor need RAID?
No, if the above two reasons, redundancy and performance are not relevant. Yes if either or both reasons are relevant.
Re 1. Redundancy
Every mechanical disk will eventually fail, sometimes on the first day of use, sometimes only after several years of usage. When that happens, all data on that disk are lost and the only solution is to get a new disk and recreate the data from a backup (if you have one) or through tedious and time-consuming work. If that does not bother you and you can spare the time to recreate the data that were lost, then redundancy is not an issue for you. Keep in mind that disk failures often occur at inconvenient moments, on a weekend when the shops are closed and you can't get a replacement disk, or when you have a tight deadline.
Re 2. Performance
Opponents of RAID will often say that any modern disk is fast enough for video editing and they are right, but only to a certain extent. As fill rates of disks go up, performance goes down, sometimes by 50%. As the number of disk activities on the disk go up , like accessing (reading or writing) pagefile, media cache, previews, media, project file, output file, performance goes down the drain. The more tracks you have in your project, the more strain is put on your disk. 10 tracks require 10 times the bandwidth of a single track. The more applications you have open, the more your pagefile is used. This is especially apparent on systems with limited memory.
The following chart shows how fill rates on a single disk will impact performance:
Remember that I said previously the idea behind RAID is to have a number of disks co-operate in such a way that it looks like one big disk. That means a RAID will not fill up as fast as a single disk and not experience the same performance degradation.
RAID basics
Now that we have established the reasons why people may consider RAID, let's have a look at some of the basics.
Single or Multiple?
There are three methods to configure a RAID array: mirroring, striping and parity check. These are called levels and levels are subdivided in single or multiple levels, depending on the method used. A single level RAID0 is striping only and a multiple level RAID15 is a combination of mirroring (1) and parity check (5). Multiple levels are designated by combining two single levels, like a multiple RAID10, which is a combination of single level RAID0 with a single level RAID1.
Hardware or Software?
The difference is quite simple: hardware RAID controllers have their own processor and usually their own cache. Software RAID controllers use the CPU and the RAM on the motherboard. Hardware controllers are faster but also more expensive. For RAID levels without parity check like Raid0, Raid1 and Raid10 software controllers are quite good with a fast PC.
The common Promise and Highpoint cards are all software controllers that (mis)use the CPU and RAM memory. Real hardware RAID controllers all use their own IOP (I/O Processor) and cache (ever wondered why these hardware controllers are expensive?).
There are two kinds of software RAID's. One is controlled by the BIOS/drivers (like Promise/Highpoint) and the other is solely OS dependent. The first kind can be booted from, the second one can only be accessed after the OS has started. In performance terms they do not differ significantly.
For the technically inclined: Cluster size, Block size and Chunk size
In short: Cluster size applies to the partition and Block or Stripe size applies to the array.
With a cluster size of 4 KB, data are distributed across the partition in 4 KB parts. Suppose you have a 10 KB file, three full clusters will be occupied: 4 KB - 4 KB - 2 KB. The remaining 2 KB is called slackspace and can not be used by other files. With a block size (stripe) of 64 KB, data are distributed across the array disks in 64 KB parts. Suppose you have a 200 KB file, the first part of 64 KB is located on disk A, the second 64 KB is located on disk B, the third 64 KB is located on disk C and the remaining 8 KB on disk D. Here there is no slackspace, because the block size is subdivided into clusters. When working with audio/video material a large block size is faster than smaller block size. Working with smaller files a smaller block size is preferred.
Sometimes you have an option to set 'Chunk size', depending on the controller. It is the minimal size of a data request from the controller to a disk in the array and only useful when striping is used. Suppose you have a block size of 16 KB and you want to read a 1 MB file. The controller needs to read 64 times a block of 16 KB. With a chunk size of 32 KB the first two blocks will be read from the first disk, the next two blocks from the next disk, and so on. If the chunk size is 128 KB. the first 8 blocks will be read from the first disk, the next 8 block from the second disk, etcetera. Smaller chunks are advisable with smaller filer, larger chunks are better for larger (audio/video) files.
RAID Levels
For a full explanation of various RAID levels, look here: http://www.acnc.com/04_01_00/html
What are the benefits of each RAID level for video editing and what are the risks and benefits of each level to help you achieve better redundancy and/or better performance? I will try to summarize them below.
RAID0
The Band AID of RAID. There is no redundancy! There is a risk of losing all data that is a multiplier of the number of disks in the array. A 2 disk array carries twice the risk over a single disk, a X disk array carries X times the risk of losing it all.
A RAID0 is perfectly OK for data that you will not worry about if you lose them. Like pagefile, media cache, previews or rendered files. It may be a hassle if you have media files on it, because it requires recapturing, but not the end-of-the-world. It will be disastrous for project files.
Performance wise a RAID0 is almost X times as fast as a single disk, X being the number of disks in the array.
RAID1
The RAID level for the paranoid. It gives no performance gain whatsoever. It gives you redundancy, at the cost of a disk. If you are meticulous about backups and make them all the time, RAID1 may be a better solution, because you can never forget to make a backup, you can restore instantly. Remember backups require a disk as well. This RAID1 level can only be advised for the C drive IMO if you do not have any trust in the reliability of modern-day disks. It is of no use for video editing.
RAID3
The RAID level for video editors. There is redundancy! There is only a small performance hit when rebuilding an array after a disk failure due to the dedicated parity disk. There is quite a perfomance gain achieveable, but the drawback is that it requires a hardware controller from Areca. You could do worse, but apart from it being the Rolls-Royce amongst the hardware controllers, it is expensive like the car.
Performance wise it will achieve around 85% (X-1) on reads and 60% (X-1) on writes over a single disk with X being the number of disks in the array. So with a 6 disk array in RAID3, you get around 0.85x (6-1) = 425% the performance of a single disk on reads and 300% on writes.
RAID5 & RAID6
The RAID level for non-video applications with distributed parity. This makes for a somewhat severe hit in performance in case of a disk failure. The double parity in RAID6 makes it ideal for NAS applications.
The performance gain is slightly lower than with a RAID3. RAID6 requires a dedicated hardware controller, RAID5 can be run on a software controller but the CPU overhead negates to a large extent the performance gain.
RAID10
The RAID level for paranoids in a hurry. It delivers the same redundancy as RAID 1, but since it is a multilevel RAID, combined with a RAID0, delivers twice the performance of a single disk at four times the cost, apart from the controller. The main advantage is that you can have two disk failures at the same time without losing data, but what are the chances of that happening?
RAID30, 50 & 60
Just striped arrays of RAID 3, 5 or 6 which doubles the speed while keeping redundancy at the same level.
EXTRAS
RAID level 0 is striping, RAID level 1 is mirroring and RAID levels 3, 5 & 6 are parity check methods. For parity check methods, dedicated controllers offer the possibility of defining a hot-spare disk. A hot-spare disk is an extra disk that does not belong to the array, but is instantly available to take over from a failed disk in the array. Suppose you have a 6 disk RAID3 array with a single hot-spare disk and assume one disk fails. What happens? The data on the failed disk can be reconstructed in the background, while you keep working with negligeable impact on performance, to the hot-spare. In mere minutes your system is back at the performance level you were before the disk failure. Sometime later you take out the failed drive, replace it for a new drive and define that as the new hot-spare.
As stated earlier, dedicated hardware controllers use their own IOP and their own cache instead of using the memory on the mobo. The larger the cache on the controller, the better the performance, but the main benefits of cache memory are when handling random R+W activities. For sequential activities, like with video editing it does not pay to use more than 2 GB of cache maximum.
REDUNDANCY(or security)
Not using RAID entails the risk of a drive failing and losing all data. The same applies to using RAID0 (or better said AID0), only multiplied by the number of disks in the array.
RAID1 or 10 overcomes that risk by offering a mirror, an instant backup in case of failure at high cost.
RAID3, 5 or 6 offers protection for disk failure by reconstructing the lost data in the background (1 disk for RAID3 & 5, 2 disks for RAID6) while continuing your work. This is even enhanced by the use of hot-spares (a double assurance).
PERFORMANCE
RAID0 offers the best performance increase over a single disk, followed by RAID3, then RAID5 amd finally RAID6. RAID1 does not offer any performance increase.
Hardware RAID controllers offer the best performance and the best options (like adjustable block/stripe size and hot-spares), but they are costly.
SUMMARY
If you only have 3 or 4 disks in total, forget about RAID. Set them up as individual disks, or the better alternative, get more disks for better redundancy and better performance. What does it cost today to buy an extra disk when compared to the downtime you have when a single disk fails?
If you have room for at least 4 or more disks, apart from the OS disk, consider a RAID3 if you have an Areca controller, otherwise consider a RAID5.
If you have even more disks, consider a multilevel array by striping a parity check array to form a RAID30, 50 or 60.
If you can afford the investment get an Areca controller with battery backup module (BBM) and 2 GB of cache. Avoid as much as possible the use of software raids, especially under Windows if you can.
RAID, if properly configured will give you added redundancy (or security) to protect you from disk failure while you can continue working and will give you increased performance.
Look carefully at this chart to see what a properly configured RAID can do to performance and compare it to the earlier single disk chart to see the performance difference, while taking into consideration that you can have one disks (in each array) fail at the same time without data loss:
Hope this helps in deciding whether RAID is worthwhile for you.
WARNING: If you have a power outage without a UPS, all bets are off.
A power outage can destroy the contents of all your disks if you don't have a proper UPS. A BBM may not be sufficient to help in that case.

Harm,
thanks for your comment.
Your understanding was absolutely right.
Sorry my mistake its QNAP 639 PRO, populated with 5 1TB, one is empty.
So for my understanding, in my configuration you suggest NOT to use RAID-0. Im not willing to have more drives in my workstation becouse if my projekts are finished, i archiv on QNAP or archiv on other external drive.
My only intention is to have as much speed and as much performance as possible during developing a projekt
BTW QNAP i also use as media-center in combination with Sony PS3 to run the encoded files.
For my final understanding:
C: i understand
D: i understand
E and F: does it mean, when i create a projekt on E, all my captured and project-used MPEG - files should be situated in F? Or which media in F you mean?
Following your suggestions in want to rebulid Harms-Best Vista64-Benchmark comp to reach maximum speed and performance. Can i use in general the those hardware components (exept so many HD drives and exept Areca raid controller ) in my drive configuration C to F. Or would you suggest some changings in my situation?

Is the Hardware and Software enough/good for my needs

I've been reading these forums and a few others and am concerned about somethings and hope some of you can help with these concerns:
Some background and info:
1. I've ordered a Dell XPS 720 H2C which as a Intel Core2 Extreme processor QX6700 (3.46GHz,,Overclocked) w/Quad Core Technology and 8MBcache, 4 GB RAM, Dual 768MB NVIDIA GeForce 8800GTX, 1.5TB RAID 0 HDD and a secondary 500GB SATA 3GB/s (No option for a RAID 0 secondary HDD, Windows VISTA ultimate OS.
2. Will be buying/upgarding the Production Premium CS3 package. (currently only use PhotoShop CS3 and Flash CS3).
3. I have a Canon XH A1 prosumer video camera (I'm an amature photographer/videographer not a professional. Software is my forte).
My questions at this moment are to do with hardware software capabilties and workflow.
My first project (of many I hope) is a make some corporate videos in HDV format for online marketing purposes (kind of like the videos Adobe have for CS3 - http://www.adobe.com/creativelicense/) and possibly to produce DVDs of the same.
My first question is; Given the hardware and software, will I be able to do what I need? I really hope I don't have to go buy any more hardware. I don't mind having to do one or two more steps. to achieve the end goal (initially).
Starting with the mode to shoot in (for the purpose stated above), what is my workflow going to be?
i. What is the best mode to shoot in? (24f, 30f, 60i)
ii. How do I get the video from the MiniDV tape onto my HDD and then into Premier Pro.
iii. I need to be able to compisite multiple HDV clips to produce the final cut. Is the hardware and software good for this? On a scale of 1 to 10, what can I expect in terms of productivity.
I've heard elsewhere that Premier Pro just don't produce true HD quality results. Is this earlier versions.
What format/compression and dimension is the best for online viewing (I want to retain the HD quaility as far as possible.)
Thank you all for listening and hope to hear your opinions.
Shiv.

Steven,
Thank you for your quick reply and information there in. The video is very nice too. Great angles and composition.
So I guess, I'm going to have swap my drive and re-install my OS when the machine arrives.
I'm not going to be able to capture directly to my desktop (due to poratability reasons). So is there I way in Premire CS3 to uncompress the HDV from the camera and store it in my HDD in uncompressed format? I don't mind having to do this extra step each time if the post production experience is going to be better.
I've heard a lot about Aspect HD from you and others here as well as other forums. I'm not very video savvy yet and don't understand a lot of the vocabulary used :). I've been to their website and don't get what their products are supposed to give me either (I guess their audience understands exactly what they are saying).
What I do get is it decompresses the MPEG 2 to saves it to yout HDD for editing purposes. However, I would have thought the Premier Pro CS3 would have that capability as part of the product, no?
I'd also like to use footage that is not HDV as well as photos/images (composits) but still retain the final cut to be HDV quality. Is this possible and if so, what does it do to the editing experience/performance?
Will I be able to output the final cut back to my camera's Mini DV tape (without having to buy Aspect HD)?

Error: Windows Vista failed to start. A recent hardware or software change might be the cause

PLEASE HELP!
My Lenovo SL500 is not working at all - I get error: "Windows Vista failed to start. A recent hardware or software change might be the cause"
I tried the following on my Lenovo:
Windows repair menu = "windows cannot be repaired"
Lenovo Rescue and Repair
Rescued my files from Hard-drive (copied to external hdd)
Restore System = Failed
Diagnose hardware = HDD passes all tests
Don't know what else to do with = Boot from another device ? Access BIOS?
Because I do not have the windows vista install disks
I purchased and downloaded the recovery disks from neosmart.net
The neosmart windows vista recovery disks DO NOT WORK = Error is "Unable to find any valid Windows partitions on this computer".
The Hard-drive exists because I was able to back-up files from HD through (Lenovo Rescue & Recovery Rescue files). So there is a hard-drive.
I don't know what to do next?
Last resort is to Factory Restore via either the Lenovo R&R or Windows Vista Recovery Disks (neosmart)?
Will I still have windows?
PLEASE HELP!

Hi, Josemne
Yes, if you can restore the system through Rescue & Recovery, then you will still have WIndows on your machine, but all your files will be deleted from the hard drive. Luckily, you have already saved those files elsewhere. I would recommend trying to restore the system and see if that works.
Best,
Adam
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Keyboard problems: hardware or software?

The keyboard on my iBook G4 has dead keys, not all in a row but grouped on the right side of the keyboard (they include the enter key, 'l', the comma, and three or four others). There's no obvious damage to the keyboard (I've lifted the keyboard out and inspected the connector, and nothing looks cracked or broken).
Is there any means to tell if this is a hardware v. software problem? I can use my logitech keyboard and mouse with the iBook (in fact, I'm doing that now). I've restarted, repaired permissions, zapped the PRAM and run other maintenance scripts with no success.
Thanks!

I don't have a firewire external hard drive or a bootable backup (I do have a Time Machine backup to a USB hard drive, but I don't see that I can boot from that external drive). I did boot from the OS10.5 disk, but of course there's nothing (so far as I can see) that allows me, once booted, to test the keyboard -- i.e., no text edit.
I can use my external (logitech) keyboard just fine, and nothing else seems to be wrong with the computer, so I'm leaning toward replacing the keyboard (I'm not against that anyway, just on the grounds of preventative maintenance). So, a related question: what's the best way to be sure that I buy the right replacement keyboard for my 1.42 GHz G4? Is the part number on the keyboard itself, or available through System Profile (I could not find it there). As always, thanks!

Windows xp pro stalls - blank screen- hardware or software problem?

Hi Guys,
My system is about one month old and has been awesome in performance and graphics.
Suddenly it (windows xp pro) stalls after flashing the windows loading screen and it goes blank. Looks like a software problem?
I am posting on this forum because when I check cmos, no hard drives are registered.
I can't get into safe mode, can't get past the administrator/user screen because no mouse operates here and can't select icons with the keyboard.(No admin passwords were set up anyway)
Booting from CD, repair console doesn't work because it can't find any hard drive.
Reluctant to do a complete reinstall because of precious stuff on the hard drive.
Using f8, "last known good..." just gives the same blank screen.
Using floppy boot, no other drives are recognized.
If my root directory has been wiped out by a virus or something, how come it gets past post and starts to load windows? If it's merely the graphics driver or similar not loading, how come the cmos shows no hard drive?
Is this a hardware or software problem? Any help much appreciated.

THE ANSWER !!
Hi Guys,
I finally got to talk to the guy who set up this system and he said that it is normal for RAID drives not to show on BIOS/CMOS. 'Think of it like a vrtual drive' he said. When the black and white initialization screen shows something like: 'Nividia Stripe-healthy'...then THAT is the hard-drive.
He said that as long as Windows was getting to the loading screen, that means that the computer itself was functioning okay, so don't worry about BIOS, the problem is a file corruption in windows, or virus etc.
Also he said that when trying to use recovery console or reinstall windows, because the system can only read the RAID drives through a SCSI interface, you have to load the Nvidia SCSI drivers from floppy by pressing f6 when asked to at the bottom of the pale blue screen (from Windows cd boot), before trying to do anything with windows (or windows will just tell you it can't read the drives, as it did before with me.)
So in the end, I reinstalled windows by that method and everyting seems fine so far. YAY!
Thanks you people for being kind enough to help someone out. I really appreciate it.

Update hardware and software Qosmio G30-198 for hight performance

Good morning,
I have a Qosmio G30-198.
I Have to use Autodesk Civil 3D program in the laptop.
It is a CAD program that requires a lot of ram and a high speed data transmission with the HDD's.
For this, it is absolutely necessary to update hardware and software for to use Civil with good performance.
I need to buy and install SSD HDD, install more RAM (what is the maximum allowed in this computer?) and I need to install Win 7 Professional 64 bit.
Please,
if someone can tell me how I can further improve performance of the laptop, please tell me.
I do not know what steps I have to keep.
Can you help me?
Thank you so much.

>.. what a disappointment
Why? How old is your notebook? At this time 4GB was the same when you use 8GB today.
We have mobile machines with limited upgrade possibilities.
> It is better to install hardware or soft ware? (Win 7 Proffesional)
To be honest I dont understand this question. You should upgrade RAM to the maximum level and install Win7. Im pretty sure it will work well on this old Qosmio.
If you need your notebook for some specific operations like usage of Autodesk Civil 3D program you dont even need all drivers or specific Toshiba stuff. the main thing is you have most important drivers, tools and utilities.
> I read in a post that it is necessary to change the video driver and install a diferent that the original one.
Fact is that Toshiba recommends usage of own drivers only. Toshiba offers tested and adapted drivers for usage on mobile machines. These different drivers can help notebook owner to have better graphic performance and this new driver will force graphic card to offer more power but at the same time you must understand that more performance results with more heat. Due to specific design it is very risky for notebooks.
Have you ever cleaned up your notebook? I can imagine it is pretty much dust inside.
> Do you think if I install G50 driver it will work in my G30?
Unfortunately I cannot comment this. Just be careful with this.

Raid - Hardware or not ?

I am trying to configure a Mac Pro system, and I am wondering if the RAID hardware is worth the £500 ish cost (UK) - I have seen little in the way of comparisons between using the software RAID and the hardware approach.
I think what I want to do is to have a mirrored configuration, with striping over that, over a 4 disk system.
Can anyone point me in the direction of any benchmarking that would help me decide ?

Are you sure you didn't see any threads, links, or articles?
Did you look at Barefeats and AMUG yet?
How about within these:
http://discussions.apple.com/search.jspa?objID=c194&search=Go&q=hardware+RAID
You really can't do that with Apple software RAID. Easy to do with Apple RAID, or you could use RAID5.
http://www.apple.com/support/macpro/
http://docs.info.apple.com/article.html?artnum=306231
http://www.barefeats.com/hard101.html
http://www.barefeats.com/harper13.html
Highpoint RocketRAID 3522:
http://www.amug.org/amug-web/html/amug/reviews/articles/highpoint/3522/
http://www.barefeats.com/hard93.html

What hardware and software is needed to use share point 2010

Please if enyone could help!
I want to become familiar with the advantages of using excel for example simultaneusly with other users, shere point does it best for us yes??? What do I need to install or what hardware is needed to do that?
Thanks,

Here are the hardware and software requirements for SharePoint
http://technet.microsoft.com/en-us/library/cc262485(v=office.14).aspx
Paul Stork SharePoint Server MVP
Principal Architect: Blue Chip Consulting Group
Blog: http://dontpapanic.com/blog
Twitter: Follow @pstork
Please remember to mark your question as "answered" if this solves your problem.

Screen randomly flickers (horizontal lines) -- Is it hardware or software?

In the last week my macbook screen has started to flicker...
This happens when I'm surfing, working on photos, and doing other tasks...
The the flickering seems very horizontal and is completely random in the time (mostly only for a second or two a few times a day) and the amount (less then 10% of the screen 90% of the time).
I cannot tell of it's hardware or software.
What can I do to solve this issue?
*Are there any questions you could ask that could help troubleshoot this problem?*

To my experience, it is hardware problem. Screen flickering is a complex problem because it can be caused by the logic board, LCD screen or inverter. Most of the time the problem is caused by the video components on the logic board. You can connect your MacBook to an external display to narrow down the root cause of your screen flickering problem.
If you have further question or need help, you can send me an email. I am glad to reply your email.

(RAID) super geek HDD questions

I want super geeks to respond because I trust their opinions :P and I know nothing about RAID or external HDDs now adays.
I'm a video/3D animation professional and my internal HDD is clogged with crap from old clients. In turn it's not allowing me to have much fun.
I found an eSata pci-E 2-port card for about 50 bux. I've been looking at a lot of RAID HDDs that are eSata on NewEgg but a lot of them say "PC Ready." The only one I see that is "Mac Ready" is not eSata and does not give me the rpms (5100 7200). Ideally I'm looking at 1TB-1.5 TB. Does it matter that some of them say "PC Ready". One of them I saw was "FAT 32". Isn't that what Mac is?
Is RAID hard to set up? Do I really need it with eSata Speeds being up to 3gb per second? Is there a solution that is around the same as regular eSATA drives described below?
What are your suggestions and where can I find them cheapest? I'm kinda thinking I don't need RAID and this is what I've found below.
This is the cheapest eSATA raid I've found:
http://www.micronet.com/products/sr4.htm
These are the drives I've looked at so far and wonder if they are good for Mac but are not RAID:
http://www.newegg.com/Product/Product.aspx?Item=N82E16822204079
http://www.newegg.com/Product/Product.aspx?Item=N82E16822154332
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=35721 42&CatId=136
Thank you
Scott
Message was edited by: spiralof5

Maybe it would help you to become more knowledgeable about RAIDs so you can make a more intelligent decision. OS X does support software RAIDs and Disk Utility can be used to make RAID arrays from multiple drives installed in the computer. You can also purchase hardware RAID cards to use with internal or external drives. You can purchase RAID systems that can connect to the FireWire ports. Many options. FireWire systems will be slower than RAIDs using dedicated hard drives internally or connected directly to a SATA controller.
RAID Basics
For basic definitions and discussion of what a RAID is and the different types of RAIDs see RAIDs. Additional discussions plus advantages and disadvantages of RAIDs and different RAID arrays see:
RAID Tutorial;
RAID Array and Server: Hardware and Service Comparison>.
Hardware or Software RAID?
RAID Hardware Vs RAID Software - What is your best option?
RAID is a method of combining multiple disk drives into a single entity in order to improve the overall performance and reliability of your system. The different options for combining the disks are referred to as RAID levels. There are several different levels of RAID available depending on the needs of your system. One of the options available to you is whether you should use a Hardware RAID solution or a Software RAID solution.
RAID Hardware is always a disk controller to which you can cable up the disk drives. RAID Software is a set of kernel modules coupled together with management utilities that implement RAID in Software and require no additional hardware.
Pros and cons
Software RAID is more flexible than Hardware RAID. Software RAID is also considerably less expensive. On the other hand, a Software RAID system requires more CPU cycles and power to run well than a comparable Hardware RAID System. Also, because Software RAID operates on a partition by partition basis where a number of individual disk partitions are grouped together as opposed to Hardware RAID systems which generally group together entire disk drives, Software RAID tends be slightly more complicated to run. This is because it has more available configurations and options. An added benefit to the slightly more expensive Hardware RAID solution is that many Hardware RAID systems incorporate features that are specialized for optimizing the performance of your system.
For more detailed information on the differences between Software RAID and Hardware RAID you may want to read: Hardware RAID vs. Software RAID: Which Implementation is Best for my Application?

Unknown problem - hardware or software ?

I'm not sure if this is the correct place to post this, but here goes.
I have a Mac Pro G5 Dual. I have been running Tiger on my main hard drive and Leopard on my second internal drive. Both systems have been very stable. A couple of weeks ago I upgraded to Leopard on the main drive. The installation went seamlessly and I upgraded to 10.5.6.
All was fine until a couple of days ago when I turned on and found that the second internal drive had not been recognised. I ran Disk Utility and verification and repair failed so I reformatted and loaded Leopard. This seemed to go OK, but then I noticed some very strange behaviour.
I happened to have windows open showing the Desktop for both of the drives. As I created a new folder on Hard Drive 1 it simultaneously appeared on Hard Drive 2. If I trashed a folder it would also disappear on the other drive. I definitely didn't set up any RAID array.
I then fitted a brand new replacement drive in the Hard Drive 2 bay and loaded Leopard. This time the duplication behaviour had stopped, but I tried to verify the new Hard Drive 2 and it failed. Likewise Hard Drive 1 failed verification in Disk Utility running from Hard Drive 1 (It actually locked up and I had to turn off). If I ran Disk Utility from the Installation Disk it passed both drives. Other odd things were happening - some apps running slow and not quitting.
It seems to me that the problem was not with the Hard Drives, but with them being recognised. I really don't know what to think - is this a hardware or software failure? I was really concerned that there was a Logic Board or other Hardware failure so I ran Hardware Test from the Installation Disk. Everything passed OK.
At the moment both drives are operational, but I am concerned that they are failing verification. I am going to reinstall the 10.5.6 update on Hard Drive 1, but meanwhile, does anyone have any suggestions as to what might be causing this behaviour?

After reinstalling 10.5.6 all was well for 24 hours, but now trying to verify in Disk Utility produces a freeze and the mirroring behaviour is back.
Any suggestions?

New 15" Screen Issue: It's NOT a Hardware or Software Problem!!

So, just brought my PB in to an independent, certified Apple tech.
Bottomline from his perspective was that it is neither a hardware or software issue. His opinion was that Apple is putting in cheaper LCDs!!! To his eyes - ane experience - they look like the cheaper one put in many Wintel books.
That said, we can't expect a software or hardware solution EXCEPT total replacement of the LCD - which personally I don't see happening. Now we know why this version of the PB offered more features at a cheaper price. They skimped on the screen!!!
The good news. it is not an issue for the 17"!!
As for all of us "stuck" with one? I'm afraid, not much can be done or expected from Apple at this point. The techs are not lying to you when they say it's "within spec." For these lower quality screens it is.
So, that's it as far as I'm concerned. Question answered. Not the answer I wanted to hear. But, it is the one I expected. It will be interesting to see if Apple uses these screens on the next release of PBs.

Not sure that the LCD screen is so cheap. The lines are not produced by bad packaging of the pixels units, because they fully disappear when using pure colors, and are just apparent in mid tones.
My guess is that this has something to do with an inadequate coupling btw the video board and the screen. This does not mean that this can be repaired in keeping the same hardware configuration. This rather means to me that the screen deserves a more adapted piece of equipment to work with.
I have an exemple of a low price Dell LCD screen at home (and an exemple of very good Sony as well). The Dell displays faint lines, but they do not disappear on the right sausage boy when moving the crankycat safari window. The Sony is just perfect.
Hope is not totally gone..but I did send back my powerbook for a refund just in case there is none.

Freezing and Rebooting issue - Hardware or Softwar...

Sorry if this has been asked before...but...
Is the freezing and rebooting issue caused by a fault in the Hardware or Software...?
Can someone from BT please explain just exactly what is going on.
Thank you,
wdp

sarahoxford wrote:
Just been on live chat as we are fed up of freezing up, random reboots and failed recordings. Usually happens on Gold, Sky Sports - the non freeview channels. Advice from Geetesh was factory reset thus losing existing recordings, stating rather optimistically that this 'will resolve the problem'. When pushed on freezing and failed recordings issue Geetesh said recording of 'internet channels is in a test phase so won't be able to record'?? But we have recorded on gold, fox for example - response is that it won't always work, only for some customers.
The advisor was getting confused. The bit about recording broadband channels still being in test phase only applies to BT Youview boxes. The recording functionality has been available for broadband channels on the BT Vision+ boxes since they launched last January.
To answer the original question. The occasional freezes and reboots are caused by the New Look software (possibly in conjunction with associated system changes on the BT servers). Many of us had years of trouble free viewing using the Classic software on the same black BT Vision+ boxes. It was only when we were upgraded to the New Look software that all the troubles began. If however, you are getting such problems many times per day, or even many times per hour that could indicate a hardware fault.

RAID 5 - hardware vs software questions

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