Alright, so I have a geforce 2 MX 400, which goes with 2x/4x AGP, now my question is this: Would I be able to replace it with a 4x/8x video card?
depends on your motherboard, if you built it look up the specs if it is a brand name pc than call them up and ask them.
His motherboard may support AGP 8X. I'd have to see your motherboard specs to find out though. I'm running a 128mb ATI Radeon 9600 8XAGP. Soon to be 256mb ATI X800 XT PE.