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Fornothingelse

macrumors newbie
Original poster
Feb 13, 2008
17
0
Hi everyone, I just joined the forums but I have been watch for the past year or so.

Well anyways, I just purchased the Mac Pro (early 2008) 8X2.8 stok config. I also ordered 2 extra gigs from OWC just to start off. I received the memory and installed it as to instructions. (2 stock in riser A, 2 OWC in riser B)

Here is my problem:

• The machine will only recognize 2 gigs max! I removed the stock ram and intalled the OWC into the stock config and it worked fine. So then I grouped the memory again and re-installed, only to have it reading A riser and not the other (saying that riser B is empty). Then I tried switching risers and it read 1stock ram and 1 OWC ram.

Does anyone know what this could be? It seems like the memory is ok, just not wanting to work w/ the other set.

Thanks,
 
did you buy 800mhz or 667 mhz RAM from OWC? the early 2008's ship with 800, and you can't mix 800 with 667, it all has to be one or the other.
It sounds to me like you've either got some motherboard issues, or you've got RAM of 2 different speeds.
 
Make sure you are putting all the ram in SLOTS 1 & 2 on each riser. If you have tried both memory in both risers and are still only seeing the memory in the top riser, then I would call Applecare and see what they say.
 
I installed the ram in dimms 1&2. Also, the ram is 800 MHz. I guess I will just have to call AppleCare.
 
Have you tried putting the factory memory in slot 1 of both risers and the OWC in slot 2 of both risers?
 
Have you tried putting the factory memory in slot 1 of both risers and the OWC in slot 2 of both risers?
Yeah... the manual recommends putting the original DIMMs side by side in riser A (slots 1&2) and then the additional pair side by side in riser B (slots 1&2). Then 3&4 of A and 3&4 of B if you have more pairs.
 
Remember that the biggest RAM gets priority in the risers.
eg:
2x2 riser A
2x1 riser B

Riser A alaso gets priority over B
eg:
2x2+2x1 riser A
2x2 riser B
 
Mine had to be reseated once before it would recognize but that's mentioned in the OWC manual.

So your Apple ram won't play nicely with OWC? If anything, I think OWC should resend you some new modules. Apple will just tell you to sod off and buy the extra ram from them.
 
Yea, I was affraid to call Apple, so I figured I would try another set before I go that route. I sent back that ram last night!
 
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