Is it at all possible for a motherboard to destroy a power supply, causing the supply, hard drives and peripheral cards to spark & smoke? This is what's happened to my other K6-2 350 Mhz system. I then bought a new power supply. After installing it, I'd get a green power on light but nothing else would work. After exchanging it for another unit, I got a few sparks from the power supply unit and got sparks & smoke from the hard drive & several peripheral cards. The store where I got the power supply tried to tell me that it was the motherboard that fried both new power supplies and that the units they'd sold me were in good working condition. BTW They gave me a 350 Watt power supply even though the original in my ATX box was only 250 Watts. Any feedback/suggestions would be greatly appreciated.