I've an old Compaq D510 SFF PC(Intel Pentium 4 2.0 ghz,512 mb sdram, western digital wd200 20 gb hdd). It's motherboard is a Compaq 0788h. Currently I'm using an nVidia GeForce 4 mx 420. I'm looking for a nice decent card(agp 4x). Anyone who's been inside this Pc knows there's limited space for expansion so the card ought to be small like the geforce4. Can anyone help me out? Thanks.