Hi~ I have a computer with the following specs amd phenom triple core processor 8450 i think... 2gig of ram ati HD4800 series 512mb graphics card 420W power supply 320gig hdd Ive been having this problem lately that I i use my computer for about 2 or 3 hours then if i try to restart it it wont go past the bios loading screen....however if i leave it for about 30mins to an hour it goes fine again untill i turn it off again....now i thought that this could have been a harddrive problem so i went and got a new harddrive and as i was trying to install windows 7 (needed to reboot to do install), it wouldnt get past the bios screen again.....so im back to square 1...Im thinking it could be a power supply problem so i was going to go and buy a new psu. But i thought some one here might know wat is going on so i dont have to spend any more money than i have to. Or it could be that my graphics card is fried....hopefully not its only about 1 year old. Thanks
Try to run Prime95 or any other stress testing software for about 15-30 minutes and see if the computer hangs. If not, try to restart it. Maybe some freak load accumulation (temps? although not very likely) is causing you computer to freak out. I would open up the case, clean any dust out, maybe reseat the video card, RAM, any other expansion card - check for bad caps (check out the pics on the rightmost column of the page)
edijs is absolutely right,shut down pc,remove card,ram,cpu,pull out all the connectors(wires from the psu)vacuum the mobo thoroughly,blow out whatever dust has accumulated,take out the fan and heatsink of cpu wash and clean,blow dry with vacuum if possible,clean the fans of the psu too,vacuum blower again.finally reset all the parts,making sure all the wires are fitted properly and not loosely connected,ram clips are properly set in etc.then finally power back on.if its not a defective mobo or ram problem/cpu overheating,everything should work fine.all the best.