MOre than 7 GN of RAM

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Level 1

69 points

MOre than 7 GN of RAM

Hello, I recently bought 16GB of RAM from OWC. Everything was fine for about 1 week. Then I started to get all king of crashes and, more specifically, kernel panics. In about 1 year and a half the computer was totally stable with the standard apple 1 GB.

I've tried a lot of different combination and my conclusion is that if I only put in 8 GB of RAM the mac pro is TOTALLY stable.

Have anyone else experience this? I wish I could use the f

Mac Pro 2.66, Mac OS X (10.4.9)

Posted on Jan 25, 2009 9:24 PM

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Answer 1

marokero

Level 1

135 points

Jan 25, 2009 9:43 PM in response to Yvon Couture

Have you tried reseating each memory module, and/or shuffling them around (since I assume they are all the same exact module)? I also bought 16GB of ram from OWC, and at first things worked well, then on the second time I reboot System Profiler told me I had only 12GB instead of 16GB. I reshuffled the modules around and never had a problem since - it's been 7 months already. Hope that helps.

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Answer 2

Yvon Couture Author

Level 1

69 points

Jan 25, 2009 9:51 PM in response to marokero

I had the same expience too. Like one of the crash, and don't ask me why, it rebooted automatically, and it showed 12 GB. I'll try your suggestion. That's my next step.

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Answer 3

Yvon Couture Author

Level 1

69 points

Jan 25, 2009 10:12 PM in response to marokero

The only thing I was worried about is that I took the cheapeast memory available from them. Should I have bought the more expensive one?

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Answer 4

marokero

Level 1

135 points

Jan 25, 2009 10:38 PM in response to Yvon Couture

Which memory set did you get, the 4x4GB or 8x2GB? I bought the later. If shuffling the modules around doesn't do anything, perhaps you can exchange them since OWC offers a lifetime replacement warranty.

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Answer 5

Yvon Couture Author

Level 1

69 points

Jan 25, 2009 10:59 PM in response to marokero

I bought 8 X 2. I already email OWC. I'm waiting for their answer For years I bought things from them and it's the first time I run into problems. That memory mishap reminds me of my old dual 1.42 G4 that would crash all the time with kernel panick.

Tomorrow I will test new ordering of the memory. Now with 8 GB no crash in 3 days. I really need the 16GB because I use a lot of sample in Logic Pro.

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Answer 6

Yvon Couture Author

Level 1

69 points

Jan 26, 2009 5:24 PM in response to Yvon Couture

Today I shuffled the modules around. Now the system only sees 12 GB out of 16. Riser A slot 3 and 4 were reported as empty. I the shut down the Mac Pro and switched the cards. I mean I put the lower one on the top slot and the top one at the bottom. After restarting the computer the system still sees only 12 GB, but this time on Riser B slot 3 and 4.

Is that an indication that that riser card is deffective?

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Answer 7

marokero

Level 1

135 points

Jan 26, 2009 7:50 PM in response to Yvon Couture

Try switching the modules on those slots. That's almost exactly what happened in my case. If all fails, contact OWC for replacement.

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Answer 8

Yvon Couture Author

Level 1

69 points

Jan 26, 2009 10:07 PM in response to marokero

After a few restarts and reshuffling only the lower riser modules the system now sees all 16 GB. However, I still need to see if it will start having those kernel panics again. If it does I'll leave riser B slot 3 and 4 empty to see if it's stable at 12GB.

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Answer 9

Network 23

Level 6

12,333 points

Jan 26, 2009 10:12 PM in response to Yvon Couture

Yvon Couture wrote:
The only thing I was worried about is that I took the cheapeast memory available from them. Should I have bought the more expensive one?

That is probably not a guaranteed cause of the problem. I also took their cheapest Mac Pro memory and it's been running flawlessly for over 2 years.

If you got a bad RAM stick, it was simply the luck of the draw, not because you bought their cheapest.

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Answer 10

Yvon Couture Author

Level 1

69 points

Jan 26, 2009 10:19 PM in response to Network 23

Thanks, I now suspect the riser card also. In any case I'll see if it crashes again. Usually those kernel panics happen within 2 or 3 hours. At 8GB with any of the modules I bought the system was rock solid.

I'm crossing my fingers.

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Answer 11

Yvon Couture Author

Level 1

69 points

Jan 27, 2009 6:16 PM in response to Yvon Couture

Well... it's been a day without a crash. Shuffling the module and re-sitting them seems to have work so far.

Thanks

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Answer 12

marokero

Level 1

135 points

Jan 28, 2009 9:22 PM in response to Yvon Couture

Glad things have worked out.

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Answer 13

Yvon Couture Author

Level 1

69 points

Jan 28, 2009 9:50 PM in response to marokero

So far so Good. 4 Days without a kernel panic, 2 restarts and all 16 are still being recognized. I'll see on the longterm, but untill now it seems ok and I am happy.

Thanks!

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