USB Devince not recognized error

[brainwave89]

After replacing my power supply from a 450w Antec ps to a 500w Antec power supply I've had unusual responses with my USB devices. I replaced the power supply on Monday and then installed SP 3. My usb keyboard and mouse have always worked throughout thise ideal. I hooked up my Simpletech external drive and it wasn't recognized in the front 3 usb port but was recognized in the ones in the back.
My flash drive was recognized in both the front and back. I uninstalled SP 3 and the devices were working except the front ones with the external hard drive. I then restarted the computer with SP 2 and then my flash drive and external drive was not recognzied. I get a USB device was not recognized system tray message.
Ok, I then installed SP 3. Same result. I updated the BIOS of the Intem D915GAV mobo and ran sfc /scannow. The keyboard and mouse still work along my usb printer but not my flash, external hard drive nor my Belkin 7 usb port hub.
I also unplugged the power cable to the Antec box for over an minute without any luck.

Any suggestions on getting my USB ports working again with a flash drive and external hard drive would be helpful.

 

[Sid6]

Go in to bio's and see if the Plug & Play settings are on...You did set up the Bio's after the install of the PSU...Right? also if that is not the case go back to the bio's you did have before and see if that helps.
Sid~