Hi Guys and Dolls ok I have 2 Hp Dx 5150 athlon 64 one sff and the other is a full tower but both have the same spec's. Both are single core. 4 gigs of memory 1 gig per slot all the same speed ect. Ok I have tried to upgrade the video from onboard to a pci express Sapphire HD 2400 pro and a Msi Ati Radeon 4750 The computer finds either the cards and my Monitor lights up but it takes 10 minutes for it to even get to the f10 page to enter bios..My systems lags right out...It will go into windows in a bout a half hour and find all the drivers for each card but the system it self lags out.. any one know why.. I haven't upgrade my bios flash for it.. and when i went to the hp page for compatible hardware such as my video both are listed there..but i can not fix the lag