Question why can't i use my keyboard on system setup?

[ikyungg]

so i'm trying to fix my grandpa's pc:
dx58so mobo
i7-930

when i cleaned his pc and tried to turn it on, it automatically boots up in System Setup now i cannot use the keyboard to set it up. motherboard doesn't have ps2 port

 

[rgd1101]

try different usb port?