The heatsink I originally had on my processor wasn't cutting it, it was running about 60C. I got a new one, along with some thermal paste, I applied the thermal paste (thin layer) put the new heatsink on, I've done this before, so I'm not new to this. Afterwards however, I power it on, ALL the fans start, including the one on the heatsink, I have a yellow light come on, on the motherboard (Gigabyte). But then after 3 seconds it powers off, completely. I never get a picture on the monitor, I've powered it on about 3 times, each time powering off, I've tried a diff power supply, I'm at a complete loss here, I know I installed it properly, I removed the heatsink and put it back on, and double-checked everything, still same thing. Immediate Help Requested! Thanks! Here's some specs: Athlon XP 2000+ Cooler One Heatink, with Silver Paste 256MB DDR GIGABYTE 7VRX VIA-KT333 DDR W/S GeForce 2 MX 400

Don't know the MoBo but, maybe the bios are setup if it does get a tack pulse from HS Fan it shuts down. Could be your problem. Then again just an idea.