I installed  4gig sticks ram [PC6400] on my DV9608nr HP laptop . Bios only sees 4gig !! Windows 7 ultimate x64 sees 7.7gig and uses it with a significant performance increase !! Of course ram clocks down to 634mhz. I thought this laptop only supported 4gig limit. Seems as though Bios doesn't support 8gig, but the motherboard does. Is this a performance bonus for the plagued older HP laptops ?? I am a happy camper Any explanations or comments would be appreciated.