fans run after shutdown

Since two days, after shutting down my computer, all the fans in my computer (case fans, cpu fan, power supply fans) are still turning but slower then usual. Also, the drive led flash.

This is pretty weird, I did not changed anything in my computer recently and I have this power supply hooked up in my case since 2002. I also have the same mobo since that date and never got this situation. Usualy, when I close my computer, my fans stop.

I thought that maybe my computer can be on "stand by" or "hibernate" but when closing it I see : Logging off, saving setting and Windows is shutting down. I can ear it close but still ear a little noise (the fans turning).

Appart of that, my computer is going very well, I am not loosing any power or anything else. To close totally my computer, I use the power switch on the power supply.

Anyone have an idea on what cause this problem?

 

When you turn the switch on the power supply back on do the fans come on? It sounds like a mobo issue.

 

Yes, they do not long after I have turn the switch off. But if I wait a little longuer, the fans don't run.

 

This is either a motherboard issue or a power supply issue.

Are the fans connected to the power supply or to fan connectors on the motherboard?

If they are connected to the motherboard, then I'd say it's a motherboard issue. If they are connected to the power supply it could be either still since in ATX and BTX supplies the motherboard controls the power supply.

If they are connected directly to the power supply you're drives are still recieiving power as well, although it may not be enough to make your hard drive spin or your optical drive open and close. I'd try replacing the power supply first since it would be the cheaper option.