This seems to be a problem.
I can't get past the Platinum screen - it won't recognise the DEL key, and the leds on the keyboards I've tried do not lite up for Caps Lock, etc.
Seems to be a power problem with the ps/2 ports
Some have had success using ps/2 to USB adapters; one especially said Belkin adapters worked
Just built mine, and my Neo Platinum (754 socket) board from ZipZoomFly does not recognize my keyboard. I don't know if anything else is an issue, since I can't get past the Platinum screen. I've tried the various variations of disconnecting PSU, disconnecting MOBO power connections, etc., with jumpering the CMOS to reset it.
I'm going to get a ps/2 - USB converter tomorrow to see if that fixes the problem.
Here is a related thread for reference: related threadanother oneand the mother of them all