I'm sure you all get these a lot, but this keeps happening and I'm pretty much out of patience and options here. My computer will shut off during certain CPU intensive processes. For example today I was trying to record an audio file on my computer and after 5 min it shut off, and it wouldn't even turn right back on, i had to unplug the PSU, and plug it back in before it would turn on again. I tried to record the file again and it shut off again....other times it will shut off when i play a simulation game, or try to encode videos for DVD. Here are my system specs AMD Athlon 64 3200 Gigabyte K8NS mobo 2 X 512 mushkin DDR 400 memory ATI Radeon X700 AGP video card SB live sound card WD SATA 160 gb hd Thermaltake 450 W PSU I tried running memtest and it would shut off then I swapped out the memory and it still shut off, so then I figured it wasn't the memory it must be the temp. So I figured out that the CPU was running pretty hot so i bought a good copper heatsink and arctic silver and that seemed to solve the problem. Fast forward about 6 months to today and the computer start shutting down again. I don't know where to go from here, at this point I just want to scrap the whole thing and start with a new pre-built system, also if i decided to take this to a computer repair store do you think they would be able to fix it, and how much would they charge, any ideas?