My setup was a K7T266 Pro mobo 512 Mb PC 2100 Ram 40Gb hd and a GeForce 4 4200 128Mb with AGP8. This system had been running fine, but I decided to upgrade my mobo and case as my current psu was only 300W. After installing the new mobo (Asus A7V8X) and case (with 400W PSU) booted up and ran fine, CPU temp was around 51 c. After playing some games for around 30 mins the P.C died, I thought the mains had gone off at first. After investigating the problem a dead psu was diagnosed. The P.C would work fine with my old 300w psu althought I didnt try playing games with it. Got a new psu from the suppliers re-installed it and the same thing happened again, it booted fine but died after 30 mins gaming. Tried my substitute psu again and it wouldnt boot...after disconnecting and re-conneting everything I eventually managed to boot the pc but had to underclock the cpu to get it to run. Instead of running at 1650Mhz its running at 1250Mhz. With these cpu settings the P.c runs fine and I have played games for a while with no problems. As I have to try and sort these problems with the suppliers eventually does anyone have any suggestions what could have caused/be causing these problems?

I find it unlikely that I have had 2 brand new faulty PSU'S. But the system had been running without any problems pre mobo and case upgrade.

Im assuming that the faulty PSU's have now damaged my cpu...does this appear plausible given my explanation? Im not new to building systems but have never had a problem like this before...any help or advice would be gratefully received.

CPU is allright. They either function or they don't,

in between somewhere is not a given. I see you are

now running with a bus setting of 100Mhz. Ever had

any previous problems with the RAM?


Yes it is possible to come by 2 bad PSU's. Especially

if your vendor came by these within the same batch. Same

brand, model, etc.


I feel a person needs to come by a strong PSU that

will hang in there and then procceed to correct the other

problems.


Asus is famous for reporting temperatures too high. Sometimes

as much as +10 degrees. Do you have temperature shutdown

control enabled in BIOS? What temperature setting?


In other cases I've seen where the system had to be run at 100Mhz

rather than 133MhZ, the Mboard had to be replaced by RMA.


Luck.


RD.

Thanks for the reply, I was using temp protection setup in the bios, threshold was 60c. I'm presuming if the pc shutdown as a result of hitting the threshold it would reboot when cooled down. This didn't happen in my case as both times the pc shutdown it was as a result of psu failure. Luckily I have an older system with a 1Ghz athlon cpu and pc2100 ddr ram, I can swap these out with my newer system to test the cpu and ram. I have never had any ram problems previously but I will check it out tommorrow...Im just trying to isolate the problem before I go back to the psu/mobo suppliers.

Tried the ram from the faulty system in my second pc and it ran fine with a 133Mhz bus speed...so it would appear that the ram is fine, as you stated that cpu's either work or dont it would appear that I now have a faulty mobo as well as a faulty psu...oh the joys of computing :)