I am upgrading my pc using my old ATX case with a new motherboard which is ECS KM400-M2. The cpu is AMD XP 2800+. The pc would work for a few minutes or seconds and then just shutdown by itself. The day before yesterday, I posted this question in this forum and an expert had provided with some suggestions on this problem: It seems that something wrong with the power supply and the cpu temperature. I definitely appreciated that. Before I throw more money onto this computer (I really don't like to do so), could somebody help me on this issues: 1. Do I need a more powerful power switch? Right now, I have a 350kw power supply and someone suggest me to buy a 400kw one. 2. I actually bought and installed a new case fan. I connect the pins to the motherboard. However, when the pc is starting, from the BIOS, I couldn't see its speed and the temperature. Is that a problem? What's wrong and Why? Please help! Thanks very much in advanced!