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User profile for user: Tomek S.
Tomek S. Author
User level: Level 1
8 points

Mac Pro 3.1 problem with the memory banks

Hi,

maybe someone will be able to help me because suddenly made me a strange action from the banks of RAM.


My comp is a Mac Pro 3.1 (Early 2008) 2x2,8 GHz Quad-Core Intel Xenon. I have installed on board 10 GB of RAM - 4x2 GB on one plate and 2x1 GB per second (the first two slots).

Everything worked well, but I bought these bones

http://allegro.pl/16gb-4x-4gb-ecc-ddr2-667-pc2-5300-fb-dimm-gw24mcy-i4839023642. html

and ...


... The case looks like this:


yesterday:

- Loaded "new" memory to a computer

- Turn on the computer and ... nothing - not detect memory: /

- Bones communicated unto the second plate, I changed places, I put into individually ... nothing

- I pulled out, loaded the old 10 GB, I turn on Mac - and all was OK

- I put the "new" memory to the Mac Pro 1.1 - the same action - nothing

- I pulled out, I put the old memory - all OK works on old as it should

- I called the seller outlined the situation, I said that in my memory does not work, I sent and no problem


but today:

- I run a Mac Pro 3.1 in the morning, but it works very slowly

- Up to, check, restarts ... all the time very slowly works

- Check the memory status and there sees only 2x1 GB (the day before it was all OK)

- Pull out the card with RAM, check to see if it's OK, I charge, turn on MAC and again see only 2x1GB (inserted 4x2 GB + 2x1 GB)

- Line up, changing, scheming, and at the moment I came to the same situation as in the attached screenshot (inserted on the 1st chart plate in slots 2 and 4, the memory of 1 GB)


I tried to put the RAM in different ways, but only works like on screenshot.


Been turning so that the computer can not see on both boards (Mac Pro 3.1) slots 2 and 4?!?!?

I would add that in the Mac Pro 1.1 everything works as it should - because I wonder if what I bought those memory spoil anything, but it seems to me that immediately after loading the old memory would be something wrong - and yesterday went without equipment problem and saw the whole 10 GB, and besides would probably also something about 1.1 been turning?


I do not know what to do, no ideas: /


Help.


P.S.

Resect p-ram has not helped.


P.S.2

Sorry for my english 🙂


User uploaded file

Posted on Dec 12, 2014 6:54 AM

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9 replies
User profile for user: Johnb-one
Johnb-one
User level: Level 6
9,180 points

Dec 12, 2014 9:48 AM in response to Tomek S.

that's okay, Tomek, I'm sure your English is better than my Polish. The Mac Pro is very picky when it comes to bones. It has to be DDR2, PC-5300, FB-DIMMS, ECC, 240 pins, 800mhz and it has to have big heatsinks. Little ones won't work. You can use 667mhz ones, too, but they will be a bit slower. here's a photo of

the correct onesUser uploaded file.

on the bottom. They also, as you have seen and know, must be installed in a certain order, and in pairs. I think Hynix only does up to 2 gig sticks. Crucial, Kingston and others may make bigger bones (ah, more meat, bigger bones). Looks like you bought some bad bones. Take 'em back to the butcher and get the other ones. Your Mac Pro will thank you. Here's the diagram for Mac pro ram installation. User uploaded file

and that's it.

John B

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User profile for user: The hatter
The hatter
User level: Level 9
61,001 points

Dec 14, 2014 6:55 AM in response to Johnb-one

The Mac Pro is very picky when it comes to bones. It has to be DDR2, PC-5300, FB-DIMMS, ECC, 240 pins, 800mhz


5300 means you have 667MHz - that works but it is not the 800MHz Apple calls for.

Not sure how or where you end up pulling two different specs together here.


What is happening is you have defective memory.


With just one set it can be installed two ways: A1 : B1 or it can go into A1 : A2


Some people have bad "messed up" boards and have had to use A1 : B1 and A3 : B3 - no known reason why (was not the Riser and new RAM did not help)


FBDIMMs tend to run HOT, too hot without large memory heat sinks, however here in USA new FBDIMMs (with heat sinks also too) now run cooler and better design. And have gotten cheap. A 2GB DIMM goes for about $12.


You can use 667MHz but if you do - and those work fine and only small 4% slower, then all the memory runs at 667.


Your front side bus is 1600MHz (800MHz x 2) is why you want to use DDR2 6400

http://www.amazon.com/2008-PC2-6400-Buffered-FB-DIMM-MA970LL/dp/B007GB1I7K/

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User profile for user: Tomek S.
Tomek S. Author
User level: Level 1
8 points

Dec 14, 2014 2:51 PM in response to The hatter

These memories (5300) I wanted to install a Mac Pro 1.1 (It is in my house).


Mac Pro 3.1 is the place where I work. When I bought a pack of memory (i call them "new"), and arrived at the business address I wanted to see if they work. The computer (3.1) prior to the exchange to the "new" memory was installed "old" memory in the configuration: card A: 1, 2, 3, 4 (4x2 GB) and card B: 1, 2 (2x1 GB). A total of 10 GB.


"New" and "old" memory I installed in the configuration: A: 1, 2, 3, 4 (4x4 GB "new"), B: 1, 2, 3, 4 (4x2 GB "old"). I turned on the computer and... nothing happened. The LED above the power button blinked, but the computer is not turned on. I turned off the computer and pulled out the "old" memory, the configuration looks like this: A: 1, 2, 3, 4 (4x4 GB "new"), B: empty all the slots. I turned on the computer and the same - nothing happened, the LED above the power button blinked, but the computer is not turned on.


I pulled out the "new" memory and put it in the "old" in the same configuration as they were at the beginning - a total of 10 GB. But when you turn on your computer in menu "About this Mac / memory" I saw only 2 GB!


After many attempts I managed to arrange storage in such a way that in the picture, in the configuration: A: 1, 3, B: 1, 3 (4x2 GB) and the computer now sees 8 GB.


But really, the card is inserted A configuration memory slots: 1 (2 GB), 2 (1 GB), 3 (2 GB), 4 (1 GB) and the computer sees only as bones with a capacity of 2 GB. These 1 GB can not see.


If I put the bones in the configuration of slots (it does not matter whether the card A or B - the computer behaves the same): 1 (1 GB), 2 (2 GB), 3 (1 GB), 4 (2 GB) is a computer sees only the bones 1GB!


It seems like that: my computer did not see now slots 2 and 4, on both cards (A and B)!

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User profile for user: Grant Bennet-Alder
Grant Bennet-Alder
User level: Level 10
133,105 points

Feb 2, 2016 8:22 AM in response to Tomek S.

The Mac Pro with Xeon processor uses Memory Error Correction. At startup, ANY errors cause the RAM slot to be declared "Empty" and will not be used by the System.


The next time you start up, it MAY test OK, but it is still not right.


If your new RAM DIMMs sometimes FAIL when installed with all new ones, they are not the correct ones for your Mac. Fail sometimes is the same as fail all times.


The RAM DIMMs you bought may be perfectly good, but if they do not work in your Mac, they are dead to you.

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Mac Pro 3.1 problem with the memory banks

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