Mixing RAM speeds in Mac Pro 3.1

I recently bought a used Mac Pro 3.1 early 2008 2xquad core 2.8 gHz. It came with 6 1 Gig 667 MHz in RAM. This Mac takes 800 MHz- can I fill one of the risers with 4x4 Gig 800 MHz while temporarily keeping 4 1 Gig in the other riser? I realize all will (should?) be running at 667 until I switch to all 800 MHz; but can they be mixed as long as they're on their own riser card? I can't afford to replace all the RAM at once, and am hoping to upgrade in waves. An extra 4 Gigs isn't much but it would really help for a short time.

I thought I/we already went through this a day or two ago, not you? then someone else.
Check it out.
Same over on MacRumors and links to ebay and Amazon
Mac Pro 3,1 memory question
And yes you can mix and match - as long as each paired set and if even one set is 667 then the memory controller will downlclock for all.
http://www.barefeats.com/harper5.html

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Mixing RAM Speeds...No Ben Hur jokes please ;)

Is it ok to mix RAM speeds. Somehow I purchased some RAM awhile back that was PC2-3200U-255 for my Quad. Oops, I never noticed that is wasn't what came with the computer, the 4200-444. Well, I just bought some more RAM at 4200-444, and noticed that I had varying speeds. Will this variation pose any problems?
Thanks!!

Thanks for the link Josef. Very informative. Unfortunately, I am still confused (my permanent state).
So I checked my invoice from my purchase and it looks like I purchased 5300 instead of the 3200 that is showing in "System Profiler". I opened up the computer and indeed it is 5300. So, is mixing the 4200 and 5300 a no no? Is the 5300 in fact being read as 3200? And doesn't the other RAM automatically run at the lowest speed, no matter what speed is highest?
Thanks, sorry that I don't get it. I did searches and am still confused.
Slow learner,
fatlanglois

Can a power mac g5 run on the same ram as a mac pro?

I have a Power Mac G5 and want to buy some new rame and i was wondering if it ran off the same ram from a Mac Pro, Specifically 1 RX8-PC3-8500E-7-10-DO ram type.

OWC is a great source for Mac RAM:
http://eshop.macsales.com/shop/memory/PowerMac-G5-Memory

Installing medium-cost RAM on my Mac Pro

Hi everybody!
I've just bought a 2x 2.66GHz Mac Pro and it's wonderful. However, I ordered it with a minimum configuration because I thought I could find expansion pieces on the market.
Is there any problem if I install a 1GB-667-DDR2 RAM module non-ECC and unbuffered (it is to say, different from the ECC FB-DIMM from Apple, which seems to me TOO EXPENSIVE)?
I've read about heating > noise troubles, but I can't really believe them. Has anyone of you tested a medium-cost (e.g. Corsair) RAM module on a new Mac Pro? Does it give good results?
I didn't find problems when looking for a 3GB/s SATA HDD, but it's difficult and -above all- expensive to buy an Apple RAM module or other brands' ones with the same technology.
Can anybody help me, please?

Shima,
To quote from the Apple site for you on the performance benefits from symmetrical RAM configurations on Mac Pro.
The Mac Pro comes with two memory riser cards, each with four DIMM slots. With a total of eight slots, you can add up to 16 GB of memory. Memory DIMM pairs should be installed evenly on both risers. This table shows Mac Pro RAM configurations that will achieve ideal performance:
Riser A contains: Riser B contains:
2 x 512MB 2 x 512MB
2 x 1GB 2 x 1GB
2 x 2GB 2 x 2GB
4 x 512MB 4 x 512MB
4 x 1GB 4 x 1GB
4 x 2GB 4 x 2GB
Note: DIMMs must be installed in pairs of equal size from the same vendor. For instance, you must not have one or three DIMMs on either riser at any time. Additionally, two DIMMs from different vendors should not be combined and used as a pair.
From tests I've read around the web, filling the slots as Apple suggests achieves a 5-7% performance boost. Whether your MacPro would even recognise ram installed randomly, or in unmatched sizes is something I do not know.
Enjoy your MacPro, I am jealous.
G5 Dual 2ghz, 3.5Gb Ram, MacPro soon I hope. Mac OS X (10.4.7)
G5 Dual 2ghz, 3.5Gb Ram, MacPro soon I hope. Mac OS X (10.4.7)

Has anyone tried Kensington RAM in their Mac Pro?

Has anyone tried Kensington RAM in their Mac Pro? I found this ram and that is far cheaper than OWC or apple.
http://www.newegg.com/Product/Product.aspx?Item=N82E16820139940
Please let me know what your experience has been with 3rd party ram.
Lester

NewEgg: " Memory returns allowed for 30 days, subject to 15 percent re-stocking fee. "
So YOU are the expert about which are the correct modules. a mistake costs you 15 percent plus shipping.
I prefer to do business with mac-centric vendor who lend me their expertise and tell me what memories work in my Mac, "Guaranteed or your money back."
OWC is one that does business that way.
Data Memory Systems does as well, and that is the outfit I use.
The last 1333 8GB module like these I bought from them came with a large flat heatsink installed. I put it in my Server. The price has fallen a bit since then, and now they are asking US$78, but "Guaranteed."
http://www.datamemorysystems.com/_apple_info/Apple_Mac_Pro_12-Core_Xeon_Westmere _2.93GHz_Memory_1632.asp

Extra RAM install on mac pro early 2008

Hello,
I have purchased and installed 8GB of ram in my mac pro. In addition there was 4 slots of RAM there already. These are 4 x 1GB totalling 4GB of RAM. With the 8GB that will make 12GB in total. However my Mac Pro can only see 10GB of RAM. I have placed the original 2 slots of (2x1GB) RAM with the new 8GB of RAM on the upper riser and the two slots of 1GB on the lower. The lower is not being detected at all. This is despite me moving them around in different slots. What is the answer? I know the RAM is operational and I know the riser trays are fine, my conclusion is that I am not placing the remaining 2 G in the correct slots. Well if anyone can help. I have seen the photo on support community of where you place RAM additional RAM and it still does not recognise the lower riser RAM.

How To Install and Remove Memory Mac Pro
https://support.apple.com/kb/HT4433

Mixing RAM Speeds

Hi there,
I posted this in the "Using Mac" forum, but unsure how to delete it, so I reposted here! I'd like to upgrade my memory. Currently, I have the factory installed 1GB RAM. Can I mix memory speeds? For example, will I be able to put 2GB in the empty slot and still have improved performance? I went on crucial.com, which recommended this, but I wasn't sure if this would be okay.
Thanks,
Rhys

I did not know that about that group of Mac's running G4, I guess I did learned something new today
What I would like to add to all of this is also that it does matter when you deal with dual channel memory like on the Mac Pro's in that case you will have to mach the same size and speed other wise it will not read correctly.
I have had misc memory size on my MacBook Pro 15" and my iMac as well (Intels) and it was working just fine, so you wont have any issues. Although Apple does recommends you to matching pair.
I hope this answers your questions,
Goran
G.

RAM upgrade makes Mac Pro run hotter? & Only recognizing 14gb (instead of 16)

Hi Everyone,
I just bought a Mac Pro 3,1 (jan 2008). It came with 8gb of 667mhz RAM and seemed to run great but because I bought this for school where I am learning music production, my instructors all said I would more than likely need to max out the RAM to get its fullest potential. On the apple website it says the max upgrade is 32GB of 800mhz speed (Mac Pro (Mid 2012 and earlier): How to remove or install memory)). That seemed pretty expensive for my budget right now so decided 16gb at 667mhz would be fine. I bought all hynix brand (2gb x8=16gb) as the apple site says to keep them all the same brand.
When I first installed, the system read that I only had 8GB. I powered down, took out the slot, reinstalled, restarted and now it is showing 14GB. It is staying at 14gb no matter what I do. I have tried switching the RAM to different slots. Also I noticed that when I would open the MP, the RAM chips are so incredibly hot that I have to wait for them to cool before trying to take them out. So my questions are:
1.) When you upgrade RAM, is the system supposed to run hotter? I've read the answer is yes...but is this safe for my computer?? I can only imagine what would happen if I had bought the 32GB 800mhz. I dont want to burn up my system. what is the average temperature that my computer should be running?
2.) Why is my system only recognizing 14gb when I installed 16gb? It is reading the RiserB's DIMM1 and DIMM2 as only 1GB. Does this have to do with the CPU overheating/overworking?
AHHHHH !!!

jariko wrote:
...I bought all hynix brand (2gb x8=16gb) as the apple site says to keep them all the same brand.
When I first installed, the system read that I only had 8GB. I powered down, took out the slot, reinstalled, restarted and now it is showing 14GB. It is staying at 14gb no matter what I do. I have tried switching the RAM to different slots. Also I noticed that when I would open the MP, the RAM chips are so incredibly hot that I have to wait for them to cool before trying to take them out. So my questions are:
1.) When you upgrade RAM, is the system supposed to run hotter? I've read the answer is yes...but is this safe for my computer?? I can only imagine what would happen if I had bought the 32GB 800mhz. I dont want to burn up my system. what is the average temperature that my computer should be running?
2.) Why is my system only recognizing 14gb when I installed 16gb? It is reading the RiserB's DIMM1 and DIMM2 as only 1GB. Does this have to do with the CPU overheating/overworking?
AHHHHH !!!
Who did you buy the DIMM's from and did they certify them as meeting Apple's thermal specifications? Does the vendor offer a lifetime warranty?
Apple has much stiffer thermal requirements than the typical PC maker does, and that includes the proper heat sinks to draw heat away from the DIMM. If those heat sinks are skimpy or not present at all, the DIMM's will run hot. For example take a close look at these DIMM's and you can see heat sinks clamped to the surfaces of the DIMM's that draw heat away from the chips and into the air flow from the Mac Pro's fans. I can't say what substituting the slower DIMM's for the correct RAM does regarding heat but it's good practice to install what the manufacturer specified.
Open System Information (Apple Menu with the Option key down) and select Memory in the Hardware group. You should see all the installed DIMM's and their status.

What 'Ram' does my Mac Pro need?

Hi gang,
What type Ram (the actual code\serial name) would go into the specs below? I have a friend who has just returned twice to the dealer because the Ram the dealer installed was incorrect. I'd like to get it right the first time. Any help would be most appreciated.
Ben
Model Name: Mac Pro
Model Identifier: MacPro1,1
Processor Name: Dual-Core Intel Xeon
Processor Speed: 2.66 GHz
Number Of Processors: 2
Total Number Of Cores: 4
L2 Cache (per processor): 4 MB
Memory: 2 GB
Bus Speed: 1.33 GHz
Boot ROM Version: MP11.005C.B08
SMC Version: 1.7f10
Serial Number: G8711209UPZ

Also, the way memory is configured seems to not always be understood; sometimes two brands don't get along. And deal with someone that sells a lot of memory to Mac market and knows the Mac Pro.
Crucial is popular top-tier w/o paying Apple price, TechWorks, OWC, TransIntl, Kingston....
Micron/Crucial, Hynix, etc, but there are a limited number of companies that really make memory and the rest are resellers.
http://www.crucial.com/store/listparts.aspx?model=MacPro%288%2Dcore%29
http://eshop.macsales.com/shop/memory/Mac-Pro-Memory
http://www.transintl.com/store/category.cfm?Category=2646
http://docs.info.apple.com/article.html?artnum=304235
Tech Note: RAM Expansion
http://www.barefeats.com/harper12.html
http://www.barefeats.com/harper3.html
http://www.barefeats.com/harper5.html

Mixing RAM Speeds In iMac G4 1GHz 17" Flat-Panel?

I'm just checking here.
I have an iMac G4 1GHz 17" Flat-Panel, Model M8935LL/A (USB 1.1 version) that currently has the standard 256MB PC2100 (266 MHz) RAM module installed in the factory slot, and a 512MB PC2700 (333 MHz) RAM module installed in the bottom (user-accessible) slot. I bought the machine direct from Apple, so despite the "official" spec (which calls for PC2100 RAM in both slots), it's obvious that Apple knows PC2700 RAM will work in that machine. My understanding is that the faster PC2700 RAM simply downclocks to accommodate the lower 266 MHz bus speed of the M8935LL/A. As I understand the DDR SDRAM spec, any DDR SDRAM (PC1600 through PC3200) module will simply overclock or underclock to accommodate the host bus speed...but feel free to correct me if I'm mistaken on that point.
I'm fixing to upgrade the hard drive to a larger capacity model. I've done it before, so I know it's no picnic. Since I have to go past the factory RAM slot anyway to change the hard drive, I figure I might as well upgrade the internal RAM to the full 1GB limit. (Yes...I know Apple says you can't exceed 512MB in either slot, so please—no remonstrances about sticking to Apple's spec. The spec is wrong.)
Obviously, it's possible to mix the two RAM speeds between the two slots, since Apple shipped the computer that way. Here are my questions:
• Is there any downside to going the other way when I upgrade the RAM—that is, putting a 1GB PC2700 (184-pin) module in the factory slot, and a 1GB PC2100 (200-pin) module in the user slot? The reason I ask is because my preferred supplier (OWC) can't supply me with both modules in the same speed.
• Is there any performance advantage in both modules being the same speed—that is, both PC2100 or both PC2700? If not, I'll just buy the one of each speed that OWC has available.
Thanks!

jjw wrote:
So, you know have 2Gb available in your flat screen imac?
Yes indeed—2GB confirmed as available by Apple System Profiler. Both modules are PC2700. Everything is working fine.
I guess I can understand why Apple discourages users from replacing the 184-pin "factory slot" module. There's not a whole lot of slack in the motherboard connector cables, so it's best to disconnect them in order to get the bottom section to lie flat on the workbench. I suppose some folks might be hesitant about disconnecting things, but it's really quite simple, and involves only three connectors. After having changed the hard drive a few years ago, replacing the RAM was a piece of cake by comparison.
A word of caution to anyone who's going to attempt it, though. There are TWO heat sink interfaces between the bottom section (where the motherboard is mounted) and the top dome. Those heat sink surfaces are coated with thermal paste at the factory, but the compound dries out over time, becoming a rubbery membrane between the heat sink surfaces. Once you separate the top and bottom sections, the membrane rips apart, and the firm connection between the heat sink surfaces is permanently gone. It's a bad idea to simply put them back together after you change the RAM module; you won't get a good thermal connection.
The solution is to scrape all of the old rubbery compound off all four surfaces (two on the bottom and two on the top section). I did it with a piece of PVC, but you can use anything with a sharp edge that won't scratch the metal surface—even your fingernails will work, unless the old compound has dried out to the point where it's hard. After you scrape the old gunk off, apply new thermal paste to all four surfaces.
The other maintenance item you can perform while you're in there is cleaning out all the dust, which accumulates in vast quantities and interferes with cooling. I vacuumed it out with a plastic crevice tool, being careful NOT to touch any of the components with the tool. Vacuuming can build up a static charge on the tool, especially in dry environments, and high static voltages aren't friendly to microprocessors. I used a securely grounded anti-static wrist strap throughout the entire operation, and even wrapped it around the vacuum tool.
Good luck!

UPGRADING AND MIXING MEMORY ON MY MAC PRO QUAD CORE DUAL 2.8 (Xeon)?

Hello,
I have a Mac Pro Quad Core Dual 2.8GHz (Xeons) with 4GB of memory (2 x 1GB Apple modules + 2 x 1GB other brand - Shown as "Manufacturer 0x855D") and now I want to fill the other 4 memory slots by adding an additional 16GB (4 x 4GB modules) for a total of 20GB of RAM.
My 2 questions are:
1.- In which order/pattern should I install these new 4 X 4GB modules along with my original Apple 2 x 1GB modules and the "Manufacturer 0x855D" 2 x 1GB modules the best way (for better performance)? - I have heard stories that if I do it improperly, I could slow down my Mac Pro...
This is how I have them configured right now:
Raiser A / DIMM 1 = 1GB (Manufaturer "0x830B") - I assume this is the Apple memory, right?
Raiser A / DIMM 2 = 1GB (Manufaturer "0x830B")
Raiser A / DIMM 3 = Empty
Raiser A / DIMM 4 = Empty
Raiser B / DIMM 1 = 1GB (Manufacturer "0x855D") - How can I find which manufacturer is this?
Raiser B / DIMM 2 = 1GB (Manufacturer "0x855D")
Raiser B / DIMM 3 = Empty
Raiser B / DIMM 4 = Empty
2.- What brand would be most compatible to work with my Apple 2GB (2 x 1GB) factory memory? Kingston? Crucial? Mushkin? iRam? Corsair? OWC? (Does OWC sell their own brand? or which one do they carry?-its not specified on their web)
Thank you so much in advance for all your help!

About RAM installation in the Mac Pro
Mac Pro memory arrangement photos
Mac Pro Memory Configuration
Memory Tests- "2008" Mac Pro
Ram should be installed minimally in matched pairs and optimally in matched quads. This means the memory modules are the same size and specifications. They should also be equipped with the Apple-certified style of heat sink.
Brand really doesn't mean much as long as they work.

667 MHz v 800 MHz RAM in a Mac Pro 3,1 (Early 2008), will it make much difference?

I know that the Mac Pro 3,1 (Early 2008) are supposed to run the 800MHz ram, but I’m aware that they also happily run the slightly less expensive 667MHz ram as well?
In the real world would you actually notice much difference between the two? Just that I have 24GB of 667MHz that I could swap over from a 2,1 model into this, or would I be better off in the long run biting the bullet and buying some 800MHz ram?
Interesting to see that OWC seem to ave some kind of exclusive deal on some 8GB 800MHz ram modules that could take the 2008 Macs up to 64GB in total!

In this case and Early 2008, 667MHz FBDIMMs have never shown to be an issue, work fine (4% hit at most, which can also be offset by using all 8 DIMM slots with four sets which improves memory bandwidth to it s best).
There have been a few 'enterprising' individuals that have had access to and used 8GB DIMMs for 32 and 64GB total memory w/o trouble but in that case you would want 800MHz DIMMs.
http://eshop.macsales.com/shop/memory/Mac-Pro-Memory#800-memory
FBDIMMs like many memory modules are not locked to a specific timing and frequency and can be backward compatible.
These from Amazon are only 2GB DIMMs but known to work in 2006-2008. When you get into 4GB the price has jumped up. And 8GB prices have been in the stratosphere, or had free access to server memory source.
2x2GB FBDIMM DDR2 667MHz @ $25
http://www.amazon.com/BUFFERED-PC2-5300-FB-DIMM-APPLE-Memory/dp/B002ORUUAC/
Komputerbay 8GB (2x 4GB) DDR2 667MHz ECC FB-DIMM (240 PIN)
http://www.amazon.com/Komputerbay-PC2-5300F-Buffered-FB-DIMM-Heatspreaders/dp/B0 05HIWD5U/
OWC 8GB FB-DIMM Memory Upgrade Kits for Apple Mac Pro 2008 Released 64GB $320
http://benchmarkreviews.com/7366/owc-8gb-fb-dimm-memory-upgrade-kits-apple-mac-p ro-2008-released/
Ideal RAM config is 8 DIMMs - offers 15% improvement memory bandwidth performance
667MHz FBDIMMs are cheap, excellent and 4% 'hit' you would never know about.
http://www.barefeats.com/harper5.html

Third party RAM for my Mac Pro

I have a 1st generation Dual-Core 2.66GHz/4GB Mac Pro desktop. I want to install 16 GB total, from a third party. I'm not very computer savvy... and I'm not sure which third party offers the ram most suitable for my particular machine, or which pairs I'm better off purchasing, etc. If anyone knowledgeable enough to put me in the right direction could give me some advice I'de really appreciate their input. Thanks guys.

You will need 667MHz FB-DIMMs. If you are thinking about upgrading to a 2nd gen MacPro, then you can get 800MHz ones. In 1st gen they will operate at 667MHz but you will be able to swap them into a 2nd gen if anything. If you are not planning to upgrade anytime soon, then forget what I just said and go for teh 667MHz ones.
If you are not planning to ever want more than 16GB RAM, then 8x2GB is a good choice. Or you can get 4x4GB.
Now, there is Apple Certified and Apple Qualified FB-DIMMs. Its basically the same thing but Apple Certified ones are much more expensive just because they are "certified" by Apple. Qualified memory is the same thing, but it has not been certified by Apple. Same reason why Apple brand memory is much more expensive. I am using qualified memory myself.
http://eshop.macsales.com/shop/memory/Mac-Pro-Memory
Hope this helps.

Having trouble with my internet speed on Mac Pro tower.

Hello all.
I just had an AirPort card installed into my Mac Pro Tower (2.66 GHZ Quad-Core Intel Xeon, with 3 GB 1066 MHz DDR3 internal memory, Running OSX 10.6.4), and the internet is running, but at a snail's pace compared to my Mac Book Pro (2.66 Ghz, Intel Core 2 duo, 4 GB 1067 MHz DDR3 internal memory, running OSX 10.5.8). I ran speed tests on both of them, the Mac Book pro is running at around 20 MBPS while the Tower is tops out at around 5 MBPS.
Anyone else having these kinds of issues? Any help would be greatly appreciated.

Mac Pro airport wireless is poor at best.
I'm going to try BearExtender. I can't hang with the internal card anymore.
Had a G5 in the exact same place as the MacPro and it worked fine.
Have a friend that recently got a MacPro and he's bypassed the airport card because of such poor performance.

Unused RAM filling up Mac Pro OS 10.9.2

I have a 2009 Mac Pro running OS 10.9.2. It has 8 processores and 24 GB of RAM. Throughout the past couple of weeks, I have been seeing the unused RAM get filled up (I use a program to monitor my RAM usage and the white 'free' area starts to progressively turn gray). The machine then become unresponsive and sluggish. I use the Terminal to purge it and all is well for a while. I need assistance to figure out what is causing it and how to fix it.
Please instruct me on which report would be beneficial for a diagnostic and how to bring up said report. Any input will be greatly appreciated. Thanks in advance.

Launch the Console application in any of the following ways:
☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)
☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.
☞ Open LaunchPad. Click Utilities, then Console in the icon grid.
The title of the Console window should be All Messages. If it isn't, select
SYSTEM LOG QUERIES ▹ All Messages
from the log list on the left. If you don't see that list, select
View ▹ Show Log List
from the menu bar at the top of the screen.
Click the Clear Display icon in the toolbar. Then try the action that you're having trouble with again. Select any messages that appear in the Console window. Copy them to the Clipboard by pressing the key combination command-C. Paste into a reply to this message by pressing command-V.
☞ The log contains a vast amount of information, almost all of which is irrelevant to solving any particular problem. When posting a log extract, be selective. A few dozen lines are almost always more than enough.
Please don't indiscriminately dump thousands of lines from the log into this discussion.
Please don't post screenshots of log messages—post the text.
☞ Some private information, such as your name, may appear in the log. Anonymize before posting.

Mixing RAM speeds in Mac Pro 3.1

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