There should be a jumper that enables/disables standyby power, did you try removing that if its on the pins ?
Or do you want to keep standby power and still kill USB power ?
I have the opus 150w with the usb power issue that drains the battery when the system is off. I have heard that there are motherboards that have cmos or jumper settings that allow you to cut power to usb devices when the power is off. My question is specifically what mini-itx motherboards allow you to do this. Right now I'd most like a pentium M motherboard but would like to hear about all motherboards that allow this.
Epia M9000, Opus150w,
512mb, 120hd, Lilliput TS 7in, GPS mouse, IRMan/Pioneer Steering Remote,