Why Does USB Device Power Stay On After Shut Down?

by Tom
(SLC Utah)

Need some advice: why does the USB device power stay on after shut down of computer?

I was given a bunch of old computers and parts and using them to build my own computer!!

First, let me say that when I was a preschooler my mother would find,and give me, broken things to fix. Things like vacuum cleaners,radios clocks,toys - just about anything electrical.

So I learned about power supplies and drives etc. And (thanks to this site) I built a computer. It took me about 1 year to get the build done, operating and online. And the only money I spent was for a legal disc of Windows XP (no regrets). I did find that I had more fun building it than using it!

The only problem that I'm really having is that when the computer shuts down, the B+ power going to the USB ports and mouse port stays on. I guess that I need a schematic for the switching SCRs. Are they in the motherboard or the power supply? If anyone can help me on this, please email me.

tom.skippy at yahoo.com Thanks.