First attempt at system building gone very wrong. Any help or suggestions gr8ly appreciated.

System:
Athlon 2600+ (333 Retail w/ Zalman cooling)
Asus A7V600 (KT600) Awardbios Rev 1005
Connect3d Radeon 9600 AGP8x
1Gb Corsair Valueram PC3200
Win2k

Problem:
At default rated CPU speed (2.075/166/12.5x fixed multiplier), system hangs randomly 2-10 minutes into usage, sending mixed up video signal.
Prior to hang, CPU/Mboard temp<40C, CPU Vcore 1.65 stable,
Set bios back to defalts, replaced video card, no effect.
No IRQ conflicts, memtest x86 ran 9 hours no errors.
Turning CPU down to Athlon 2000+ (1.67/133) using "CPU speed" setting in bios, system stable; sisoft benchmarks run 20 times no problems.

I don't know whether to implicate RAM, CPU, or MoBo at this point.
Thnx in advance.

Try raising the voltages, v1.7 vCore, 1.7v vChipset, and v2.7 vDimm. Might be a dupe CPU, where did you get it?

My first instinct would say ram. That's almost always the first thing I check. But memtest running 9 hrs. would tend to dispute that. Might try reseating the ram anyway. Or pulling one stick at a time and running that way to see if it makes a difference.

Another possibility would be an inadequate power supply. What are you using?

Is this a fresh OS install? Are all your drivers current?

Thanks very much for the advice.
- Changed Vcore to 2.7 and 2.75, still hanging
- Unclear how to adjust chipset voltage.
- DRAM voltage changed to 2.7, still hanging.
- DIMM's re-seated, still hanging. Going to try and RMA them and pickup a different RAM, probably Mushkin PC2700, since the general impression I've gotten is that this is quite reliable. (Of course Corsair valueselect is supposedly reliable to).

My follow-up question is - if the memory swap doesn't work, should I look to swap out the mobo, or the CPU, or just live with an underclocked system?

Much obliged for any more experience opinions.

AntiM hit the nail on the head. You need a good power supply to ensure stability. If you have one, my first instinct would implicate the RAM.

Quote: Originally Posted by BigAkita AntiM hit the nail on the head. You need a good power supply to ensure stability. If you have one, my first instinct would implicate the RAM.

Ironically, I was writing my thank you response, having successfully completed 10 rounds of Sisoft burn-in with new single stick of Mushkin Blue 512MB PC2700 in place, ripping a CD at the same time - when it crashed again. I think my system is beginning to mock me.

The powersupply is an Antec "Truepower" 380W as found in their Sonata case, so it is probably reliable. Looking back at the voltage log (which was in the background at the time of crash) - rock stable (although ASUS PCprobe does not list DIMM voltage)

Might there be something I'm overlooking in the settings? Reviewing the bios, which I again set back to default, RAM timings are set automatically ("by SPD"), many of the AGP settings are/were underutilized (e.g. "fast-write", which the video card and chipset are capable of (I believe) was off, and the "Mapped Video memory" was set to 64MB (default), when it is a 128 MB video card. The ASUS "Q-Fan" utility was enabled, so the CPU fan was slow, but CPU and MoBo temps were <40 regardless.

Or is it time to implicate larger hardware (Mobo/CPU)?