Power Supply?

[Jeff Crosby <jlcrosby@xxxxxxxxxxxxxxxx>]

All,

My son's desktop PC (built by a local shop a couple of years ago) started
acting up Friday night.  Most of the time it won't come on at all, once in a
while it will boot up.  When it _doesn't_ come on, nothing comes on.
Nothing on the display, no hard drive light, no power light.

My first thought was power supply, but even when nothing else comes on, the
fan in the power supply runs.

Have you ever heard of that?  Power supply goes, but the fan still runs?

Thanks.