No advice for your lockup But I have had this piece of crap for 3 years, The mother been replaced at least 4 times.
Went into repair every 4 months
Last time as AFTER my warranty b/c I bitched what a piece of crap it was, where they completely gave notebook a once over.
This "repair" lasted 3 months.
The notebook is sluggish again, and the fan WHIRLS, one IE 6 window eats up resources.
It is a piece of junk. I wonder who was the morons that rated this a great notebook?
On a side note-- I wonder if those new motherboards will help?
Otherwise its Apple for me baby!!!