Hi Dieter, your problem is indicative of one of several possible issues.
IIRC this part is one of those combined FWH/LPC parts. Can you verify this on a data sheet?
Can you see if it is configured as LPC or FWH? I just had a real problem with one of these.
I can't look in too much detail, right now, but I will do what I can. What board is this, again? Is the part in a socket?
ron