I am having some power supply issues... A system which had been working fine wouldn't boot yesterday. It did not even POST, the fans whirred slightly & then just stopped. The system had a 500W ATX power supply. Of course I suspected the power supply & tried a 250W ps that i had in another system. It booted just fine w/ this ps. We purchased a new 500W ps & installed it. Nothing, same as the original problem. So I tested this new ps on another system & it booted right up. Put the 250W back on the problem machine & once again it booted up without a problem. I also had a 450W ps in another system so I tried that one & it too booted up. So I installed it into the case, turned it on & once again, I got nothing, No POST & fans start up & stop. This is the same power supply that booted up just a few minutes before. So once again I reinstalled the 250W ps and it booted right up. Needless to say, I am completely baffled. Why does the 250W ps work every time, the 450W worked before it was installed in the machine & the 500W doesn't boot up the system at all? Any suggestions would be greatly appreciated! If more details about the system are needed, I can supply those too.
weird one!!! try a BIOS reset, it may then remember what it is and what it's suppose to do, beyond that, i don't have a clue, but you've created a real head scratcher of a problem there, Big B is probably the best man to sort this problem out
It sounds like to me that Maybe that mother board has some kind of power stablizer on it.. Why not just use the 250 watt to solve the problem ? I agree that the motherboard should be able to handle any power supply. BUT this sounds like a real strange problem, Read on the 250 watt power supply and see if it is a SWITCHING power power supply,then read on the others.. Match up the information to see the difference.
wow kwier i found your post on a different site in march that sucks, ok so time to fix the problem. OK to me it sound to be a motherboard issue flat out, there isn't any real reason for this to happen, in the time being i would check the bios like donkey said, actually if it got reset, depenging on how old the motherboard is, it might not read the 500w power supply. I would go for a bios update and considering the PSU works in a different machine, it most likely the motherboard. Also you might have to get a new mainboard as your might be dead. Also it would be helpfull to list what you have for specs as well what you have attached to the machine, and how old is the mainboard
