Problems with new build - Memory?

[mike d]

I am trying to diagnose a problem I am having with a rig I just built. The compents are:

ABIT KN8 motherboard
EVGA GeForce 7600GT
Hitachi 160gb HDD
2x512MB Patriot DDR400 memory (1 each in DIMM1 and DIMM2 for dual channel)
Sony DVD burner
400watt power supply
AMD Athlon 64 3500+

Everything works fine until I try to play a 3d game. Usually within 5 minutes, I crash to the desktop. I do not get any error messages.

First I tried running Prime 95, I was concerned maybe the CPU/heatsink wasn't installed correctly. Within 30 seconds the program spit out a hardware error (I don't have the exact error message, something about expecting a different value).

Next I downloaded and tried Memtest +86. I received multiple errors while running test #5. At this point I figured I had some bad memory, so I began testing each 512mb chip independently to figure out which one is bad. To my surprise, both tested good in memtest, when running Prime 95, and when playing a game (BF2 in this case, which before crashed everytime, but with only one of the memory chips installed it ran without crashing, although a bit slow.) So everything runs great with only one of the chips installed.

Any ideas on why my computer crashes when both memory chips are installed?


Thanks,
Mike

[Panama Red]

When you tested the memory sticks individually, did you install them in the same slot? Or did you install them in the slots you used when both were installed? I'm wondering if one of the mobo slots is bad.

Also, what brand is your power supply? Is it a 24 pin psu on a 24 pin mobo connector?

[mike d]

I tested both DIMM 1 and DIMM2 with one stick only, and they both passed memtest. So they only fail when used together in dual channel. Next I tried putting the sticks in together in DIMM 3 and 4 (dual channel) and they failed memtest, but they woked individually in either slot 3 or 4.

As for the psu, it is a 24 to 24 pin connection.

Thanks for the help so far. I'm thinking maybe something is wrong with the mobo's dual channel capabilities? What do you think?

[Panama Red]

Possibly the mobo's DC but I'd try different memory just to be sure. Are the memory timings recognized in the bios the same as they are listed from Patriot? By that I mean, if Patriot says 2.5-3-3-6, is that what is shown in the bios when you set the memory timings to manual? Also, what brand is that psu?

[mike d]

I tried setting the memory timing manually, but it didn't help, still got the same errors. I'm going to try some new RAM as soon as possible.

Not sure of the brand name of the PSU, it came with a cheap case manufactured by ione. The PSU is labeled "Model: LPJ2"

Mike

[Panama Red]

Save yourself some future grief (or expense) and replace that no-name psu before it fails and takes some quality parts with it. It may even be that the psu isn't providing proper voltage for the memory. Check the sticky thread in General Hardware for a list of Good psu's - but stay away from Ultra.