MacPro Memory problem - Kernel Panics

[Videographer]

So I got my Mac Pro about 2 months ago and recently I started having issues with Kernel Panics on a regular basis. I have 2x512mb Apple Stock memory and 2x512mb Crucial (built for MP). When I first purchased the Crucial RAM I did get failed tests when running MemtestOSX. But after a while the tests started passing so I dismissed it as a fluke or something wasn’t seated right. So I kept using the memory and everything seemed to work properly for a while.

Then recently whenever I try to run Compressor, Memtest, or sometimes anything memory-intensive (FCP), I get the gray curtain of doom – Kernel Panic. Memtest passes with JUST the Apple RAM or JUST the Crucial RAM installed. But when both are in, I get a crash 95% of the time. I’ve tried all the riser card/ram combo I can think of and nothing works.

I brought it in to an Apple store, but in running their diagnostic tool they didn’t find the problem (of course...). They ordered some new memory and a riser card and are going to start trouble-shooting today (which will be hard if they can’t detect the problem).

Did I make a mistake going with 3rd party memory? It seems like I’m the only one this has happened to. Can anyone think of what the problem might be based one what I’ve described? I’m just worried that Apple will say it’s not their problem since the machine works with just their memory and they can’t support 3rd party stuff. The genius I spoke with seemed very uninterested in the issue (espeically after he heard about the Crucial memory - as if to say, "Well, duh, you've got 3rd party memory, what'd you expect?"). Then Crucial could say the same thing -their memory works by itself, therefore it works period.

Any comments ideas would be much appreciated.

 

[mad jew]

Yours is quite a common problem. Memory testing apps are notoriously bad at finding problems with your RAM so they'll pass almost anything, unless it's literally about to explode. Hopefully simply replacing the RAM with either some non-faulty third party stuff or some Apple stuff will get you back up and running.

 

[CanadaRAM]

Did you get the Crucial RAM before they pulled it off the market, or after they reintroduced it? 2 Months ago I'm guessing you may have got the recalled batch. Anyway, RAM never gets 'better'. If it throws errors at the start, then it'll always error (unless the problem is improper installation in the socket, of course) , so pull it immediately.

 

[Videographer]

Hopefully simply replacing the RAM with either some non-faulty third party stuff or some Apple stuff will get you back up and running.

I think you're right, but the problem is just figuring out which one is bad. It seems that they just don't like working together to me because they'll work fine seperate.

I don't think it was the recalled batch of Crucial. But I'm not sure. It has the larger heatsinks on them if that makes any difference.

 

[mad jew]

How long did you test them for? I know it's a pain in the arse, but maybe run on 50% RAM for quite a while (a day of heavy use, maybe two), just to see if you can narrow down to a bad chip (if that's even the problem).

 

[ironjaw]

How long did you test them for? I know it's a pain in the arse, but maybe run on 50% RAM for quite a while (a day of heavy use, maybe two), just to see if you can narrow down to a bad chip (if that's even the problem).

sorry if i did not read your post (i just skimmed through)

have you tried http://peloche.smugmug.com/photos/91752872-O.jpg

the RAM has to be correctly postioned in the riser.

 

[Mezzanine224]

I've been having major kernel crashes on my Mac Pro recently. I have 1 GB of Apple RAM and 2 GB of 3rd party RAM.

I took out the 3rd party RAM and haven't been having any crashes at all. So I took it back to the store to get it exchanged. My fingers are crossed that the new stuff will work.

 

[Videographer]

How long did you test them for? I know it's a pain in the arse, but maybe run on 50% RAM for quite a while (a day of heavy use, maybe two), just to see if you can narrow down to a bad chip (if that's even the problem).

Actually I had been running on just the Crucial for a little over a week and had no problems at all (other than a painfully slow workstation). I did Compressor encodes, FCP editing, everything (sometimes at the same time). No crashes.

Which reminds me, there was one time when I tried booting up on just the Apple RAM and the computer only saw 512mb. Perhaps one wasn't seated right, but that could be a clue that the Apple stuff is to blame. I can't remember, but I think memtest may have crashed once when testing the Apple memory, but it was a while ago. I wish I had it to do more testing...

I'm still waiting to hear back from the Apple store. Just out of curiosity, how long does a repair typically take? It's been three days with no word. When they ordered the parts they said it would be only a couple days at the most. But then when I brought it in the guy said a week or more. That'd be pretty poor service for such a simple repair. The parts are there, let me test it...

 

[Videographer]

have you tried http://peloche.smugmug.com/photos/91752872-O.jpg
the RAM has to be correctly postioned in the riser.

Thanks for thinking of this. I'll use this chart when I upgrade again. However they were installed as specified.

 

[Jiddick ExRex]

Take some time with runnning on 2 memory sticks until the problem reappears.

 

[Videographer]

Take some time with runnning on 2 memory sticks until the problem reappears.

I would try this but the Apple store has it now. But even if I did narrow it down to Apple's memory, they'd probably want to verify themselves that it was bad. It's frustrating because I feel like I could go a good ways to solve the problem if they just let me use some fresh memory...

 

[Videographer]

Finally fixed the problem. Apple had it for 4 days, had it crash once and replaced a stick of memory. Unfortunately they replaced the wrong stick as after I got it home it crashed after 2 minutes of FCP rendering and iPod movie encoding.

So I told them they didn't fix it, but that I was going to figure out the problem by swapping out different sticks of memory and running memtest (which gets it to crash regularly within 5 minutes). Sure enough, it crashed only with the OTHER stick of Apple memory -the one they left in.

Thankfully the Genius at the Apple store agreed to take my diagnosis of the problem and just swap out stick for stick without bringing my computer in a 3rd time only to have them not find it again (their hardware test is pretty piss poor if it couldn't find a problem like this).

Just as an FYI the stuff that went bad had a bluish Aquamarine color to it. This is what shipped in the standard config. The replacement memory (and what the tech said all the memory is now) is a brighter green stick. The heat sinks are the same it's just the stick itself. It's interesting to note that aside from the stickers the new sticks look exactly like the Crucial stuff.

Anyway, that's the end of my story (hopefully... all tests are passing so far). Thanks for your help.