Default Nexus S 4G Won't Be Recognized By PC

Hey Guys.

I recently flashed the wrong firmware through ODIN onto my NS4G (Nexus S Original bootloader.tar instead of 4G). This in turn left my phone with constant No Service. Now I'm trying to flash the right one, but my phone won't be detected by ODIN, or my PC. It only shows that it's Charging (USB).

I've tried installing Samsung USB Drivers from them and PDANet Drivers. None of them worked.
Please help. Thanks