I made back in x-mas a pc of the following standards:
512mb sdram 133mhz
geforce 4 mx 440 64 mb
pc chips 510 mobo
i have added a bigger heat sink on the vid card and i have got an adequate heatsink on the processor. and yet while i play games at 16bit+ vid quality. games like unreal tournament half life q3 etc etc the pc goes for about 5 minutes and then reboots. i check the temp of the chips and there about 50 degrees. my brothers runs smoothly at 70 degrees. what the hell is going on.