No response from any USB or PS/2 ports

Hello,
I recently had to replace the motherboard and processor in my pc after the old ones died. Me and a friend plugged everything in fine, only it blue screens when it gets to the XP loading screen, which was to be expected and would require a simple repair of the windows installation.
EXCEPT the motherboard doesnt recognize any form of mouse/keyboard/usb device plugged into it, so i cant boot from CD or check the bios as none of the keys will work. upon turning on it flashes up with 'keyboard interface error'. ive tried both USB and PS/2 keyboards and mice, as well as USB sticks and MP3 players, and nothing gets a response. the keyboard lights do not flash when the pc is turned on. The motherboard is an AMD AM2NF6G-VSTA. i changed from Intel to AMD if that helps. i'm still using the same HDD i had with my Intel motherboard. all of the keyboards and mice i have tried work in other PCs. none of them were wireless. the PC is not currently plugged into the internet via ethernet or wireless. I have tried removing both battery and changing jumpers to reset CMOS but this had no effect.
I cannot access windows, the BIOS, the XP install CD or any drivers. The PC boots with an Ubuntu live CD in it, but the keyboard and mouse still do not work.