motherboard 48 bit capable

I have been struggling to get 250 gb harddrive recognized with old abit b6 and kt7a motherboards.Winxp wo'nt let me install sp2 suggests my xp serial is pirated.What I am wondering is (I have a pentp4 2.8 cpu off dead motherboard) is there a board prefrably abit or msi that supports 48 bit processing has agp graphics slot that would allow me to use kroll big drive enabler and might this enable me to see and use large drives. I would be very grateful for any imformation which would help me with this problem, or point me in the direction of where I might find a web site to get further explanation on 48bit proccessing and motherboards which support this.:confused

 

I think you'll find the 48 bit processing all depends on the BIOS version that is being used on either of the two mobo's you mention so if the BIOS is too old itmight not work.