Instability issues

[exit-reality]

I recently bought an Athlon XP-M 3000+ off eBay. I managed to find the correct FSB/Multiplier ratio (266x16.5=2.2Ghz), but my system is unstable at that setting (i.e. my games crash after about 5-10 minutes of play). I have to back the speed down from 2.2Ghz to 1.8Ghz to get my system to run stabily. This is very disappointing, as I've heard about the overclocking potention of XP-M chips and I was anticipating pushing the chip beyond 2.5Ghz easily. Any insights as to why this is happening?

Complete Specs:
CPU: Athlon XP-M 3000+
MB: ASRock K7VT4A+
RAM: 1GB DDR400
Video: 256MB Radeon x800GTO AGP 8x
HDD: Samsung 80GB w/8MB buffer
Sound: SoundBlaster AudigySE

 

[magouster]

Have you increased the VCore?

 

[exit-reality]

I could try that, but I'm hesitant as the CPU should be able to run stabily at 2.2Ghz without a VCore increase. I'll give it a try though.

 

[magouster]

The Athlon XP-M runs with a stock speed of 1.8GHz, so you would definitely have to increase the core voltage to get it to run at 2.2. Make sure you have good cooling, and take overclocking it in really small steps, with regular testing in Prime95. Oh, BTW, your math at the top does not add up. (266*16.5=4389)

 

[Nitestick]

Oh, BTW, your math at the top does not add up. (266*16.5=4389)

double pumped 133mhz FSB

 

[exit-reality]

This page lists the frequency and multiplier of a 3000+. Supposedly it runs at 2.2Ghz, but the page could be off as well. Running the chip at 1.8Ghz has my BIOS detecting the CPU as a mobile 2500+.

And as the poster above me said, 266 total FSB equals 133mhz double pumped. To get correct math you'd want this: 133*16.5.

 

[magouster]

To get it at 2.2, have you tried running it with a 200FSB, and 11 multi, like the normal Athlon XP 3000+ ? You would see better system performance that way, since you would at least have your RAM run at the full PC3200 speeds, instead of downclocked to 133MHz. Just a thought.

 

[exit-reality]

No luck with 200x11.

However, I find something very interesting. I ran Prime95 at 200x11 for almost 7 hours straight with no errors popping up, but when I ran my SAT prep software (which is by NO means a demanding program at all) it crashed within 10-15 minutes. The requirements on that program are rediculously low, like a 266Mhz CPU and 64MB of RAM. Something's amiss here, but I'm not sure what.

 

[exit-reality]

I *believe* I fixed the problem.

I read that my motherboard supports ONE DDR400 dimm, not two. I went into my BIOS and switched the RAM bus from 400Mhz to 333Mhz and so far things have worked fine.

I'm not sure why I wasn't having problems with my previous CPU, but this one brought it into the light. It's a little disappointing to have to run my RAM at a lower bus than what I paid for, but I think the overall performance gain will be greater than my previous setup (old CPU = Sempron 2200+).