Upgrading memory question - unbalanced / mixing memory

2006 Mac Pro. Here is what I have. 4-2 gig dimms and 2-512 dimms totalling 9 gigs of memory. What should be the order that I install the 512 dimms. Riser A: 2-2 gig dimms and the 2-512 dimms, then Riser B: 2-2 gig dimms or should all four 2 gig dimms be in Riser A and the 2-512's in Riser B? Or should I not install the 512's at all? Does it matter mixing memory sizes? Thanks for any help.
-David

Leave them out.
Use 2 x 2GB in slots 1 and 2 only on each Riser.
4 DIMMs gives best, and adding 1GB isn't worth the added latency, heat, or performance.
Symmetrical memory performance comes with quad sets / channels.
You could put them in slots 3/4, but don't.

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Neo2 Mixing Memory Question

Currently running 2x512 Crucial Ballistix in slot 1&2 stock speed 2.2.2.5 - stable. I'm desperate for 2 gigs of ram but thanks to a nagging wife and lack of funds this isn't possible yet, but i do however have 2x512 Corsair value sticks (2,5.3.3.8) in an old machine which i can take out and put with the Crucial Ballistix to make to 2 gigs (4x512). I'd just like to know if mixing them is a good idea or am i asking for trouble.
Any advice, tips are most welcome

Hello Billy,
Your wife is not nagging you. She just has great looks and excellent computer savy and does not want you to buy or mix memory sticks.
Mixing memory stick as per your plan will only cause lost system performance and instability. You have a Winnie CPU so you will definately need to run at 2T. The timngs, voltages, and chipset of your ballistix and corsair sticks are quite diversed. I own four stick of Ballistix RAM made from different batches. Crucial professed that they do not have to worry about matching dual channel pairs but my own test here reveal a 140 to 176 megs bandwidth performance difference between newer and older pairs (older better). Using this has a comparaison you can just imagine what associating ballistix and corsair would be like.
In summary Billy, unless you are an Italian noble who like self-inflicted pain, is not to mix your crucial and ballistix Ram sticks. Work on the wife instead, wine and dine her, so that you can talk her into letting you buy 2 X 1Gig sticks of PC 400 Ballistix sticks.
Good luck with the frau,

Mixing Memory Mac Pro 2.66 Xenon

Hello all!
Alright I am trying to figure the best configuration that I can afford for a memory upgrade to my Mac Pro. I am looking to spend somewhere south of $200.
I currently have the following memory configuration (3GB):
DIMM Riser A/DIMM 1: 1 GB
DIMM Riser A/DIMM 2: 1 GB
DIMM Riser B/DIMM 1: 512 MB
DIMM Riser B/DIMM 2: 512 MB
I wanted to expand it quite a bit more and see on NewEgg that they are charging appx 65.00 for (2 x 1GB) and 80.00 for (2 x 2GB). It's definitely a better price per GB to get the 2 x 2GB but would I see a large performance increase?
I have been reading on the message boards that it is best not to mix memory but it is suggested to fill all the slots with the same size memory.
I guess it just kills me to take out all of my existing memory to put in just the 4GB of new memory.
Could anyone provide any suggestions?
Thank you for your time in advance!

You have 3GB, which is on the lite side.
The ideal for that model is 4 DIMMs.
Without knowing if you are a light photoshop, or what you use it for, Apple calls 4 x 1GB for FCP (and audio apps) "symmetrical memory."
And I would look at 4 x 2GB and pull your 3GB, maybe sell it once you know the new memory is fine after a month.
Are you seeing page outs? multiple swap files?
Go to folder: /var/
Maybe you are better off with faster drives, new boot drive or for scratch. A WD 10K 150GB VelociRaptor for $180 even.

Mixing memory module of different sizes in G5-8 slot machine

is there a problem with Mixing memory module of different sizes in G5-8 slot machine
I have 2gb on four slots with 512 memory chips
Can I upgrade my memory with 1gb chips in the remaining four slots.

Hi epospiech-
Yes you can.
Instructions here: Memory (DIMMs) Replacement Instructions
Luck-
-DaddyPaycheck

Memory Question "4x1 Gig or 2x2 Gig?" what is faster?

Memory Question "*4x1 Gig or 2x2 Gig*?" what is faster?
I'm still don't know if witch to choose?
4 times 1 gigabyte Ram Memory is cheaper but if I choose for 2 times 2 GB Ram I can always beef it it later.
And is my memory faster if I'm using 4 slots with 1 gig over 2 slot with 2 gig?
I'm asking this question because I think using 4 times the memory bandwidth will be faster?
http://www.janmaartendewit.com

Hello Jan
Welcome to Apple Discussions
The iMac (Late 2009): Installing or replacing memory article and your User's Guide are pretty clear, they both say that +"You can use 2 GB or 4 GB RAM SO-DIMMs of 1066MHz DDR3 SDRAM in each slot."+ and not 1GB modules. > http://support.apple.com/kb/HT3918
To upgrade your ram you will want at least 2 more 2 or 4GB modules and add that to the current 2 x 2GB of ram. > http://eshop.macsales.com/shop/memory/iMac/DDR321.527
Dennis

RD530 Mixing Memory

I have a ThinkServer RD530 and am wanting to upgrade the RAM. I currently have two 8GB RDIMMS that I would like to continue using while adding two 16 GB RDIMMS. I have reviewed the memory rules from the HMM but have been unable to confirm either way whether this is supported. Will mixing RAM sizes (while staying constant with frequency and voltage) cause any problems? Is there a certain way I need to configure the RAM if different sizes will work?
Solved!
Go to Solution.

Hello mmunsterman,
While this response is delayed, you are able to mix memory sizes. There is no special configuration needed, just follow the instructions for installing the memory into the correct numbered slot. You can boot into BIOS and verify that your additional memory is seen.

Mixing memory modules of different sizes in a Mac Mini

I have a MM Intel Core Duo with a 1.66GHz processor and 512 MB 667 MHz SDRAM. Model Macmini1,1, 32 Bits, SMC Version (system): 1.3f4.
Anybody know if you can mix memory modules in it? I have the standard 256 modules (2) and would take one out and replace it with a 1 GB one. Can this be done?
Thanks

+Anybody know if you can mix memory modules in it? I have the standard 256 modules (2) and would take one out and replace it with a 1 GB one. Can this be done?+
Yes, you can do this. You will get a slight performance hit on video, but that will be more than offset 99% of the time by the extra RAM reducing overloading of the Virtual Memory system.
However, it is enough work to replace the RAM and RAM is cheap enough, that I'd recommend putting in two matched 1 Gig modules instead.

Mixing Memory Speeds

Apologies, wrong thread, please ignore.
Message was edited by: Rhys Bethell

Hi Rhys,
i think what you are talking about is mixing memory size, not speed. You can not mix memory speeds, especially in Macs.
You can mix memory size in most Macs. Very few Macs use memory interleaving that requires exactly the same size memory modules to work best. The iMacs allow mixing size with no impact on performance.
Go ahead, Crucial is very good with Macs and can be trusted.
Also very good is Other World Computing (OWC).
Ralph

What is the slot order for mixing memory

I have a new Mac Pro (8 core) and I installed 4 4-gig memory modules (slots 1,2,5,6). I also have 6 1-gig modules that I removed to make room for the 4-gig modules. I thought I could use 4 on the 1-gig modules in the empty bays for a total of 20 gigs. However, when I install the 1-gig modules I get a blinking power light and the machine never boots.
Am I placing the modules in the wrong slots, or is it not possible to mix modules like this?

Apple seemed to think mixing wouldn't be a problem, unless the real world is different. Did you follow the placement shown in this PDF? Might still want to try putting in only two 1 gbs though, you'll still have plenty of RAM and, according to this Apple quote,
"For optimal memory bandwidth, all six memory channels should be used, and memory should be balanced across the six channels.".
"Populating slot 4 or 8 slightly drops maximum memory bandwidth, but depending on the applications used, overall system performance may benefit from the larger amount of memory".
http://manuals.info.apple.com/enUS/Mac_Pro_Early2009_Memory_DIMMDIY.pdf
Shouldn't hurt to try... Per the manual, if your Mac blows up, Apple would have to replace it.
If you can get all your RAM to completely show up, the 4gb RAM, that's the time to monitor things and test without the added sticks. Once the Mac runs smoothly for awhile and the RAM consistently shows up, then I think that might be the best time to try the other sticks and see what happens..
Really have to make sure that RAM is seated well, and it wouldn't be a bad idea to do a SMC reset while you're in there. It sometimes unsticks, sticky RAM.
Good luck.
http://support.apple.com/kb/HT1806

Memory Question - Help!

I just started trying to import footage from a camera to my Mac. While my laptop doesn't have a ton of spare memory, I have an external hard drive that does. Question: how can I set iMovie HD 6 to use the connected external hard drive's memory rather than the memory from my laptop?
I've got about 60min of footage - but, right now, I can only import about 7min.

What you're talking about is not memory ..you're talking about hard disc space.
(Memory is the little chips inside the Mac which hold the current program which is running, etc. Hard disc storage is where you store or Save things, such as video clips and entire video projects.)
When you start a new project you'll see a window like this:
Where it shows "Where:" and the choice 'Pictures' in the little pic above, if you click on the arrowheads alongside whatever's currently showing ..e.g; 'Pictures', which is probably 'Movies' in your case.. you can then browse all the folders and hard discs on your Mac, and you can choose to store the new project on your external disc ..simple!
NOTE: Your external disc MUST be formatted as 'Mac OS Extended', and preferably be connected by a FireWire cable, not USB (..USB is too slow for sustained video transfer).
To format the external disc as 'Mac OS Extended', use the Finder to go to Applications>Utilities>Disk Utility, select the hard disc's name then click the 'Erase' tab and choose Mac OS Extended as the format for it. CAUTION: This will erase anything already on that external disc ..so if there's anything precious there, copy it across to your internal disc first.
After formatting as Mac OS Extended - it takes just a few seconds - you can then use that disc for your iMovie projects.

Memory question (yes, another)

ok, i have ddr memory rated for 200mhz, and the fsb of my processor is 333 mhz.
i was reading a thread on a corsair forum from a guy with my exact motherboard
AND memory, but a slightly lesser processor (a-xp 2500 vs a-xp2800, both barton333)
he says:
1. Motherboard is as started above: MSI K7N2 Delta2-LSR
2. Processor is Athlon XP 2500+ Barton (333 FSB)
3. CPU multiplier is unlocked so I can alter RAM to 200FSB and lower multiplier to
ensure that speed is the same.
4. Running Dual Channel mode.
i know a 1:1 ratio is best, but to GET such a ratio, is there any practical difference
between:
a) setting the memory to 166 and the ratio (manually) to 1:1
b) setting the memory to 200 and reducing the multiplier, as he's done.
i assume by multiplier he means the fsb:dram ratio - please correct me if i'm wrong.
thanks!

Quote from: Grayone on 27-December-05, 03:39:37
Having the cpu multiplier unlocked does nothing to affect the memory speed.
after closer reading, he says he's running at 2.3 ghz, by changing his processor to
200mhz * 11. something i definitely don't want to do even with my 2800!
with that in mind, i think he meant in terms of upping the processor to match
the memory (or buying faster memory to match his already oc/d psu) - and my
question is moot, for my purposes. (feel free to delete!)

Memory Question??? Where's Jocko?

I have a question on the memory frequencey showing in the bios of my motherboard it states that I have 200ddr is this correct? I have pc3500 mushkin 222. Is there a way to change this or is this just the way it shows?
amd 64 3400+
kt8 neo
34 gig wd 10000
radeon 9700 pro
2x512 mushkin 222 special
Thanks as always
Von

Well, it's a limiter and it's not
It only allows you to set your memory at a certain speed WHEN not being OC'ed....
Let me explain:
At "FSB?" 200 and set to 400DDR you get 400DDR=200MHz
At "FSB?" 200 and set to 333DDR you get 333DDR=166MHz
BUT!!!!! Pay attention now!!!!
At "FSB?" 210 and set to 400DRR you get 420DDR=210MHz
At "FSB?" 210 and set to 333DDR you get 342DDR=177MHz (not sure if they are exact but should be close, just to get an idea)
The thing is, YOU DON'T HAVE A FSB!!!!!!
The thing they call "FSB?" in the BIOS is in fact only a reference clock, nothing more.
As the Memory controller is also running at CPU speed, the memory speed is a divider from the reference clock.
Another common mistake is that people think they have a north-bridge....well you have one, and it's located INSIDE the CPU...so if you change the reference clock you also change the NB (=memory controller) speed but the dividers/multipliers stay the same.
The only thing that doesn't change as far as I know is the Hyperthreading bus, that one is locked all the time, well at least it's here on my Opteron system, and should be the same on AMD64.

Memory question on Arch x86_64. 2x2048 MB = 3950 MB?

I have a naive memory question for some knowledgeable folks. My machine has 2x2 Gb sticks which should total to 4096. When I do a free -m under Arch, it's only showing 3950. Is the remaining 146 reserved or..?
$ free -m
total used free shared buffers cached
Mem: 3950 422 3528 0 28 157
-/+ buffers/cache: 236 3714
Swap: 2000 0 2000

Thats a really good question and the result you get is normal as far as I know.
Part of it (a small part I believe) is used by the kernel, the rest of it, and this is where things are not so clear, is reserved as an agp apperture.
As far as I could tell (I have stumbled uppon that too) the problem seems to be that some bioses don't setup everything as they should.
The thing is that some devices can only handle 32bit addresses so their address is somewhere until the 4GB mark, because the bios doesn't setup the memory remapping correctly (sometimes the user has no way set anything related to memory remapping, this seems to be the case with some desktop boards and most notebooks/laptops). This memory remapping "problem" was anticipated and there are ways to properly handle that.
For some reason unknown to me (and most people that have stumbled upon this) many bioses don't setup (or allow the setup) of proper remapping. To add to the problem the kernel seems to reserve 128MB of agp aperture by default even if you don't have an agp card, this reserved address space falls in the first 4GB of addressing space therefore stealing you some memory.
I have tried to regain those MB, I have tried to recompile the kernel with a different config and I've tried several kernel boot parameters and the only thing I could regain was 64MB if I recall correctly. I can't find now what I have added to regain those 64MB, I didn't keep that option in the kernel line, 64MB were not worth the possibility of having problems later on.
I know its a pain to have that voice in the back of your head telling you that there is some memory that is being wasted, specially if you have tried a 32bit kernel with support for 64GB of address space and got 4050 MB of usable memory, but just leave it as it is, it's not worth the time and the trouble.

K7T266 Pro2 mixing memory ?!?

Hi all,
I am having a problem with mixing memory. The tech. at the computer shop say that a PC2100 and a PC2700 should work whitout problem, so I by one 512MB PC2700 !!!
Here, on my mobo, the memory check pass at boot, but WindowsXP crash when it access the PC2700 memory...
In bios, I set CAS lentacy at 2.5 and force the memory clock to 133MHz...
Note that the PC2700 work fine, alone...
You have idea ? Is PC2100 and PC2700 can be mixted ?
thanks,

Also, I can tell you that this mobo, K7T266 Pro2, is very picky about memory sticks.
Especially when mixing brands.

I have a imac 10.5.8 with 1 GB of memory. If i upgrade to 3 GB of memory will i then be able to run mountain lion ?

I have a imac 10.5.8 with 1 GB of memory. If i upgrade to 3 GB of memory will i then be able to run mountain lion ?

What year, CPU speed and screen size is your iMac?
It appears as if it's one of the 2006 models that can only take up to 4 GBs of RAM, but only 3 GBs is recognized.
3-4 GBs of RAM is really the working minimum amount for OS X, alone.
The minimum iMac hardware spec for OS X 10.8 Mountain Lion is a mid 2007 model iMac.
2006 models cannot run Mountain Lion, but can run OS X 10.7 Lion.
If you have a mid 2007 or newer iMac, my advice would be to install, at least, either 6 or 8 GBs of RAM.
OS X, by itself, to run smoothly,quickly and efficiently can use between 3-4 GBs of RAM leaving virtually no RAM for any additional applications.
If you have an iMac that can take more than 8 GBs of RAM, think of installing more if you can afford it.
Purchase reliable Mac RAM from online vendors Crucial or OWC (Other World Computing) also known as macsales.
Good Luck!

Upgrading memory question - unbalanced / mixing memory

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