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The Mac Pro First Generation is an Intel Xeon-based workstation computer manufactured by Apple Inc. The first generation model includes the machines from 2006 through 2008.

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Harpertown Pro - which RAM riser is A and which is B

Subject says it all. I can either kep switcing them around until I find out, or someone can tell me!

I have a pair od bad chips.

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The top one is riser A. Mixing RAM from different vendors will cause failure.

The Mac Pro has two memory riser cards with a total of eight memory slots.

On each card, the slots are arranged as two banks of two slots each. The computer

comes with a minimum of 1 GB of memory, installed as a pair of 512 MB

FB-DIMMs in two of the DIMM slots. Additional DIMMs can be installed in

the open DIMM slots.

DIMMs must be installed in equal-sized pairs from the same vendor and fit

these specifications:


 72-bit–wide 240-pin modules

 Maximum 36 devices per DIMM

 Error-correcting code (ECC)

NOTE  When purchasing DIMMs for use in Mac computers, make sure

that the memory vendor conforms to the Joint Electron Device Engineering

Council (JEDEC) specification. Check with the memory vendor to ensure

that the DIMMs support the correct timing modes and that the Serial

Presence Detect (SPD) feature has been programmed properly, as described

in the JEDEC specification.

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Thanks! I know all that except which was A and B. It was the pair of chiops that came with it that failed, two 1G strips...n the rest ar 2G and match.


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