Bad RAM

Ok

Buying the cheapest DDR2-800 memory available (corsair CM2X2048-6400C5) was a BAD idea. I will concider this a lesson and keep to Kingston (who never failed me) or Crucial (which I only hear the same about) in the future.

It seems the 8 GB of RAM I bought for the new machine has at least one bad bit. All things considered one bit out of 68719476736 (8*1024^3*8) is a pretty good percentage, although in this case simply not good enough.

Memtester occationally (every 7'th run or so) finds an error, it it keeps running it is the always the same address. I've tried running tests with memtest86+ but it consistently fails if there are 8 GB of memory in the machine, crashes after 50% of the first test, and during 5 hours of trying first one pair then the other found no errors. So for now I'm back to using memtester which also looks like it runs som more invasive tests (although only on the allocated memory).

At least at this point I've had no errors with the remaining 3 2 GB modules, and I've had errors whenever the 4th module was in the machine. Since the error is always at one specific address I don't think it is likely to be caused by the motherboard or the CPU. I will let the test run for a week or so though, just to make reasonably sure.

I am still debating whether I should bother RMA'ing the matched pair of modules with the defective one or whether I should just buy some Kingston or Crucial modules to replace the lot of them.

I am guessing that Corsairs test won't catch this as it only appears every 7-8 loop of memtester even when the faulty moduls is included. So there is probably a good chance that if I RMA the module they will test it, say its fine and ship it back to me.

One thing I have learned is not to save money on RAM, it is just not worth the trouble and aggravation of having to track down the error.