Is a dell dimension 4400 motherboard compatible with 8x AGP?

Answer 1

The dimension 4550 motherboard supports up to 4x AGP according to spec. However, you can use an 8x AGP card as the specification is backwards compatible. It won't take advantage of 8x throughput but it should work just fine emulating 4x.

Answer 2

While this computer does not have an AGP 8x slot, it will support 8x cards. Cards that are faster than the bus on the motherboard will simply slow down to accommodate the motherboard's speed. The only exception to this rule are the rare motherboards which have AGP 2x, because 2x uses a weird voltage and installing a 4x or 8x card could fry the motherboard and the card. Not to worry, though. Most computers and the Dell 4400 have a 4x slot.