Trouble diagnosing memory/mobo problems.

[John Williams]

I just bought some new hardware from Newegg:

ASUS P5N-E SLI LGA 775 NVIDIA nForce 650i SLI ATX Intel Motherboard

Intel Pentium D 925 Presler 3.0GHz 2 x 2MB L2 Cache LGA 775 95W Dual-Core Processor

CORSAIR XMS2 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory

It was running with:

SATA 120GB HD
IDE 120GB HD
Generic DVD-ROM
Soundblaster Audigy 2
Nvidia 7900GT
Thermaltake Silent Purepower W0014RU ATX12V 480W Power Supply
BIOS all set to defaults.

All of the older components I've had and have had running fine for at least a year and a half. The only thing out of the ordinary is that the power supply has a 20-pin connector and the motherboard a 24-pin. Of course, my old motherboard had a 24 pin, too, and ran stable and solid for a year and a half on this power supply.

I got the box, I got everything installed, and I was hit by crash after crash after crash. I popped in MemTest86 and ran it, and within ten minutes got an error. I tried again and got the same error after 30 minutes. Since then I've tried different combinations of slots, all with the same result. Whenever I have both sticks of memory in, it errors out, sometimes after five minutes, sometimes after a couple of hours.

I then tried the single sticks. Stick #1 ran for six hours and didn't get a single error. I popped stick #2 in and almost immediately got an error. I let the first run through finish, then restarted MemTest86 and let it run for six hours on stick #2 and it came back clean, and that is something like eight times through.

Summary: Two sticks, any slots, errors. Stick #1, no errors after six hours. Stick #2, error, then no errors after six hours.

I'm honestly not sure whether the problem is with the motherboard or the RAM. I don't have a second machine I can test either on. I need to return whatever is defective and get a replacement, but I can't for the life of me figure out which piece of the puzzle is causing the problem.

 

[cprince]

I'm thinking it's the RAM. Return both of them.

 

[Atheus]

Either its the RAM or your new motherboard really does need the 24-pin connector. Have you searched the web for other people using a 20-pin on that board?

 

[John Williams]

Yeah, I've looked but haven't found anything specifically for that board. I know something is bad, I just need to make sure I know what before I start the RMA process. I've already been without my main machine for almost a week. RMA the wrong part and it'll be another two before I'm up and running.

 

[Atheus]

IMO you can't go wrong buying a good quality ATX 2 power supply. Even if it doesn't solve this particular problem, it will help a lot with overclocking, and at some point it *will* be required for all new equipment.

I guess you might as well RMA the RAM too while you're at it, but I would find it strange that 2 new sticks would both be bad... normally you would expect it to work with one or the other stick...

/edit:

I just had a thought - whats the rated voltage on that corsair XMS? What does your board supply as standard? Check the BIOS.

 

[John Williams]

Only one stick has given an error, not both, but it only gave one error in 10+ hours of testing, in other words one failed test and about a dozen passed tests, while both sticks at the same time failed in a heartbeat every single time.

As far as the voltages, according to the NewEgg page, the RAM is 2.1 volts. The BIOS is set to 'auto' (with manual options), but no indication of what 'auto' sets it to. To be honest, I've never really played with voltage settings, as I rarely overclock my systems by more than a hair. It isn't something I'm knowledgeable about.

 

[Atheus]

Auto is probably 1.8V or something, so set it manually to 2.1, I bet you that fixes it

Try Prime 95 (as well as memtest86) as a stability test- it usually fails pretty quickly on bad memory.

 

[John Williams]

I upped it to 2.1 manually. MemTest86 ran about an hour and locked up solid, no errors, just a hard lock. I'm trying the test again now.

 

[RebateMonger]

Are you running anything overclocked?

 

[John Williams]

Not a thing. One of the first things I did when I started having problems was to ensure that all of my BIOS settings were set to their defaults.

 

[John Williams]

...and again. Three hours into the test, and MemTest86 locked up completely. RMA the RAM? RAM the RMA? Try a power supply first (which I may not be able to swing at all, financially?)

 

[John Williams]

I went ahead and RMA'd the RAM. I got the new RAM in today. 1 hour, 24 minutes into the test, pass 1, errors 14. Here is a photo of the MemTest86 error screen. The details don't mean much to me, but maybe will to someone here.

Unless I got two sets of RAM in a row that are bad, I'd guess it is either the motherboard or power supply. Does anybody have any idea how I'd go about finding out which? I've been without my main system now for more than two weeks, and I'm more than ready to get this solved. I don't, however, have enough money to spend it without knowing for sure.