asus p4s533 and USB

[ra77]

Hello

My config is
Motherboard Asus P4S533 (http://www.asus.com/prog/spec.asp?m=P4S533&langs=01 )

chipset : SiS 645DX North Bridge and SiS 961B South Bridge
ITE 8707F LPC Super I/O Chip

When I boot from the cd gentoo 1.4rc2 i686 I don't have have usb
no keyboard, no modem, no mouse, ...

I have tested th gentoo 1.4rc1 cd and I don't have this problem

Any idea to resolve this problem ?