So I'm building a computer with a Tyan K8SE. The power supply is a 650w redundant EPS from a Intel SC5200. I usually test the motherboard and power supply without any chips/RAM first to make sure everything is okay. I give the motherboard power and some fans start spinning -- the two exhaust fans, the 4 pin front pan, but not the two fans plugged into the connectors at the rear of the board. The lights light up across the board on the ethernet, etc. And then everything goes dead. Is this normal behavior for the board? I give it power again, and one of the power supply modules goes up in smoke (there are two power supply models in the cage). The other one is fine and shows a normal LED condition. The fried module is permanently failed and the LED light shows a fault condition for the supply. This was a new power supply. So my question is, is my board screwed? Did I do something real bad? OR was the power supply module just DOA? I can get another module, but now am I very worried and afraid to throw CPUs, RAM, etc. at the board.
As far as I can tell, tyan has power-supply problems. My k8e (different board w. only a single amd64 cpu) can't start on a 430 watt Seasonic s12-430, which has more than enough current on the 12v line to run the mobo. With 20 or so flips of the power switch it starts maybe once. The most likely flips to start are the once where there is a very brief off period. I wish tyan support would forward the observation to engineering and have them quantify the start-up current requirements. My gut feel is that one of their onboard regulators is taking way too much current to start up and pulling down the supply. It may well be a bad design that fails to keep the onboard PS logic from turning on until the main supply has stabilized a bit. -wolfgang
