well you wont get a double performance out of 8X AGP. but in system performance, only processor and RAM doesnt plays vital roles, as data has to pass through motherboard obviously, so mobo chipset as well makes difference, and 865 chipset is very powerful chipset.
Intel Core2Quad 2.66Ghz 12MB L2-Cache
4096MB DDR Kingston Hyper-X
XFX 9600GT AlphaDog
Seagate 2 X 320GB SATA2
LG L246WH Flatron 24"