Windows 7: USB Device Not Recognized

Hi guys!!

I've been meaning to ask some help regarding the issue that I am having however I was reluctant because of the fact that I fix computers for a living(I'm not that good at it though..).

I need help!!

I've been getting "USB device not recognized". I got the issue after purchasing a new power supply. I think my motherboard is fried. But I need your opinion guys. Here are the things that I did.

- went to device manager and uninstalled everything under USB controllers
- dismantled my computer to the very last piece and put everything back after an hour of waiting. (i made sure that the power was drained)
- put back my old power supply thinking that the new PSU that I bought was damaged

When I plug it in, it just says "USB device not recognized". I tried plugging my usb to a different computer and it was not working anymore. I did a little experiment and tried a good USB device on another computer. It worked well, for sure. I plugged it in mine, it said "USB device not recognized". Plugged it back in the computer that detected it earlier and BAM! It won't detect it anymore. Power surge I guess??? I am not sure...

Please Please Please.. I need your help on this guys..

1. Is my motherboard fried?
2. Is there a way for me to fix the devices that I plugged in my computer?

Many Thanks!!!

omg.. I checked my pins and i found out that I swaped the GND and USB pins..omg.. I could have prevented this to happen!! ARRRGH!!!

Is there a way for me to fix the devices that I plugged in? They won't work anymore!! HELP!!

I called the local techs here and they're willing to fix my external drive for $20.. Is that price reasonable?