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2010 MP memory 128 installed but shows 96

L

Litsnsirn

macrumors newbie
Original poster
May 26, 2018
28
3
Wisconsin
Hi all,
I have a 2010 5,1 with dual x5690's that ha 8 16gb sticks in. In the about this Mac, it is only showing 96gb and when I click over to memory, it shows two open slots, so before troubleshooting the ram sticks, I was wondering if there is anything else I should be looking at in software before going back to the RAM seller.
IMG_E03721_zpsam3ecgkc.jpg
IMG_E03721_zpsam3ecgkc.jpg
 
Try removing and reinstalling the RAM. It's not uncommon for dust to get in the slots and prevent RAM from working. Troubleshooting by moving RAM around is so easy, I don't see why you wouldn't just start with that step.
 
Mac Hammer Fan said:
Litsnsirn,
Strange my Mac Pro 5,1 6core has DIMMS with a clockspeed of 1333 MHz.
Click to expand...
I was also wondering why your memory shows a speed of 800 MHz. Any compatible sticks would show (as a minimum)1066, and usually 1333 MHz if yours is actually a macpro5,1
Can you post what memory sticks you are using? If they are all identical - what is listed on each stick's label?
 
Resetting Nvram may help. Regarding the missing ram, try swapping the ram between positions. If the slot is consistently missing, the CPU may have a bad memory channel or the memory channel on the cpu try may be at issue. Swapping the CPU's between slot 1-2 would provide a test for that case.

good luck.
 
handheldgames said:
Resetting Nvram may help. Regarding the missing ram, try swapping the ram between positions. If the slot is consistently missing, the CPU may have a bad memory channel or the memory channel on the cpu try may be at issue. Swapping the CPU's between slot 1-2 would provide a test for that case.

good luck.
Click to expand...
[doublepost=1530319328][/doublepost]Do those last two slots in the software correspond to physical slots?
 
Litsnsirn said:
[doublepost=1530319328][/doublepost]Do those last two slots in the software correspond to physical slots?
Click to expand...
Yes. If you open the side of the computer while it's running, you may see red LEDs lit near the memory slots which will indicate an error too.
 
It's likely that your RAM is simply not quite compatible. Yours has a ranking of 4Rx4, which others here (such as the talented H9826790 has suggested) say that you need 2Rx4, as the 4Rx4 typically will not clock at the full bus speed, and may cause other issues, and may simply be unreliable in the MacPro5,1 (just not a good match with the memory bus on your MacPro)
 
handheldgames said:
Any clues looking at About this mac -> system report-> memory ?
Click to expand...
Clues? The OP doesn't need much more after what was posted in post 1(showing that the RAM may not be running at full speed), and then the label in post #12 shows that the OP has RAM that is considered to be out-of-spec for a MacPro5,1
 
DeltaMac said:
Clues? The OP doesn't need much more after what was posted in post 1(showing that the RAM may not be running at full speed), and then the label in post #12 shows that the OP has RAM that is considered to be out-of-spec for a MacPro5,1
Click to expand...

Think different.
If 4r4 was 'out of spec' then none of it would show. We know 2r4 works based on some members. Extensive testing of 4r4 hasn't taken place. Apparently, this spec of Samsung 4r4 is working. o_O I tend to trust the OP's observations.

IMO... Looking at that unnecessary screen can help to determine if a memory channel is blown on one of the CPU's. I've seen many x56xx CPU's with blown memory channel(s) on ebay. :cool:
 
Slots 7 & 8 (and 3 & 4) are physically tied together. And if slot 7 is bad or empty slot 8 won't show. Slot 7 needs to be populated for 8 to be recognized and work. Looks like something is wrong with slot 7 or the CPU. Have you tried switching the CPUs to see if the issue follows the CPU? Have you tried switching the sticks around? As suggested, is there a red light beside slot 7?

Lou
 
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+1 to 4Rx4 RAM not working correctly.

OP, return the RAM and buy 2Rx4 instead and you will very likely have solved your problem.
It is very clearly incompatible with your Mac, as many others have found in this forum. @h9826790 is 100% correct here.
 
If slots 3 & 4 are working, then IMHO, slots 7 & 8 should. However, the 800 Mhz speed issue is another matter. I agree the RAM should be returned. But, it would not surprise me if the problem in slots 7 & 8 persisted.

Lou
 
Well, after all that I moved the sticks around and I'm now getting 128gb? Are there any memory stress/test programs that work for a Mac to let me know if I'm good or not?

The memory that I was eyeballing is
memory_zpswymwldx7.jpg



I'm a little confused, my 30" cinema display on the gtx 680 DVI was flashing on and off and I thought it might be related to the memory, so I was worried. I plugged a dell into the DP and it seems fine, now
 
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