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Eug Wanker · Feb 11, 2006, 12:38 AM

I bought my 1 GB DDR400 RAM stick last May, and IIRC it passed the hardware test. (I usually do this when I install new RAM, cuz I'm paranoid.) Well, the last few days my iMac G5 has shut down a couple of times for no apparent reason. Sometimes it was when I was encoding video, but also I'd just be surfing and BAM! it'd shut off. It was like somebody simply pulled the power plug. It had NEVER done this in the 9 months prior.

So I ran the Hardware Test DVD, and it said that 3rd party RAM was bad. (This is Samsung branded PC3200, CL2.5.) It's not the slot, because I moved the memory to the other slot, and the Hardware Test DVD still found the bad RAM in that other slot.

How often have you encountered this? Usually when I get bad RAM, it's bad right from the start. It doesn't usually go bad later, especially within 8 months. Heat related? The iMac runs a bit on the warm side (at up to about 72 C under load, although that is the norm for the G5 iMacs it seems).

P.S. What are some good 3rd party RAM tester apps?

P.P.S. Running Tiger with the stock 512 MB RAM really, really, REALLY sucks.

mikochu · Feb 11, 2006, 12:54 AM

It has happened to me once...on my PC. I noticed half my RAM wasn't posting. Good thing it was Crucial RAM. The RAM was over 6 years old...I still got a replacement stick for free

chabig · Feb 11, 2006, 10:08 AM

Originally Posted by mikochu

The RAM was over 6 years old...I still got a replacement stick for free

Yeah, but considering it was six years old, you probably could have bought a replacement for $20. Hardly worth the extra up-front cost for Crucial RAM, in my opinion.

Chris

Weezer · Feb 11, 2006, 12:20 PM

lots of RAM distributers have lifetime warrenties other than crucial: OWC, ramjet, datamem...

Tomchu · Feb 11, 2006, 12:48 PM

RAM doesn't go bad over time -- at least not in my experience, and not to my knowledge. What a stick of RAM ends up damaged, it's because of the motherboard it's sitting in. The voltage regulators or something of the sort could be going, maybe.

turbopants · Feb 11, 2006, 01:11 PM

I think ram is either good or bad from the start. All the ram I have installed has worked perfectly, except for one stick that consistently caused my old G4 iMac to crash after install. Brought it back to the retailer, got a new stick, and have had no problems since then.

Eug Wanker · Feb 11, 2006, 08:40 PM

I've been reading vague articles online that say that RAM does indeed go bad over time on its own in some cases, although it's not anywhere as common as bad RAM right from the outset, or improperly seated RAM.

I just hope my retailer can replace this DIMM in a timely fashion, cuz I'm ready to rip my hair out trying to use 512 MB in Tiger. I've now turned off almost all of my Dashboard widgets, and I try not to have more than 2 apps loaded at a time. And Photoshop seems to be a lost cause if I have anything else loaded.

I just hope there isn't something else wrong with my mobo causing this RAM failure, but at least the mobo check was fine, and I do have the full 3-year AppleCare too so I'm not too worried. The good news is all my capacitors are nice and flat (not bulging), and this machine has been rock stable ever since I've removed that RAM, even after hours and hours with the CPU maxed out (encoding video).

ghporter · Feb 11, 2006, 08:41 PM

I'd make sure the RAM was still properly seated; pop it out and then fully reseat it. Sometimes you'll see some movement in how DIMMs, particularly full-sized ones, fit in the socket, and a poor connection can make RAM look bad. Further, it hurts absolutely nothing to make sure everything's still properly installed, so even if it doesn't fix the problem, you're out virtually nothing because it doesn't even take much time to check it out.

As Tomchu says, RAM generally doesn't go bad. It gets broken, it gets zapped, but it usually doesn't fail. That's why so many vendors have lifetime guarantees. The issue with these guarantees is never "what's covered." It's "can you prove you got it from us" or "we'll have to double check to make sure the part is really bad. Good firms don't do that sort of childishness.

Eug Wanker · Feb 11, 2006, 08:46 PM

Originally Posted by ghporter

I'd make sure the RAM was still properly seated; pop it out and then fully reseat it. Sometimes you'll see some movement in how DIMMs, particularly full-sized ones, fit in the socket, and a poor connection can make RAM look bad. Further, it hurts absolutely nothing to make sure everything's still properly installed, so even if it doesn't fix the problem, you're out virtually nothing because it doesn't even take much time to check it out.

Yeah it was firmly seated and locked into place. And just to prove it to myself (and to confirm the slot itself was fine), I swapped the RAM slots (making sure again it was fully seated), and reran the test. Again, the Apple test detected the bad RAM (in the appropriate slot).

BTW, the quick version of the memory test consistent did NOT detect the bad RAM. Only the extended version could detect it.

SpaceMonkey · Feb 11, 2006, 09:07 PM

Originally Posted by Eug Wanker

BTW, the quick version of the memory test consistent did NOT detect the bad RAM. Only the extended version could detect it.

Yeah, from time to time I've read that the hardware test (either the quick version, or the extended version, or both) can only detect bad RAM intermittently, and should be run several times in a row to be safe.

Yose · Feb 16, 2006, 11:21 AM

I know this might be a left field answer, but maybe you should check to see what sort of voltage you are getting from the transformer on the street. I have a UPS for my desktop and a Voltage Regulator for my laser printer because I'm getting upwards of 130v instead of 115v... Apparently it slowly damaged electronics.

And if thats the case, call Hydro, they have an vested interest in fixing the problem. (Although they haven't fixed mine yet).

Eug Wanker · Feb 16, 2006, 04:41 PM

My vendor accepted the RMA no problem. They won't replace it until they get the RAM in their hands though and they're on the other side of the country, so I'm stuck with only 512 MB for at least another week.

Originally Posted by Yose

I know this might be a left field answer, but maybe you should check to see what sort of voltage you are getting from the transformer on the street. I have a UPS for my desktop and a Voltage Regulator for my laser printer because I'm getting upwards of 130v instead of 115v... Apparently it slowly damaged electronics.

And if thats the case, call Hydro, they have an vested interest in fixing the problem. (Although they haven't fixed mine yet).

Heh. I just ordered a UPS for my iMac (and Firewire DVD burner). It wasn't on a good surge protector and when I plugged in another device to the same outlet I saw the plug spark, and my DVD burn failed verification right at that moment. Luckily both the Firewire burner and iMac (and the memory inside it) are still fine.

As for the voltage thing, current iMacs from any country accept any voltage between 100-240 V, although that wasn't true for older iMacs.