Thanks monkey
Just to clear it up a bit more hoodie...
There are 6 types of expansion slots for computers...
EISA - This is so old it was only found in computers before pentium 2's and is now never used
PCI - 2nd oldest technology...is still used, but has been improved a tiny bit over the last couple of years
AGP - Graphics port that was designed specifically for video cards and it overtook performance for video almost as soon as it was released.
AMR - This was a specific port for internal DSL modems (and other networking devices) which didn't take off at all, and since stopped production.
PCI-X - This is a server expansion slot which is mainly used for RAID controllers and SCSI cards.
PCI-express - This is the 'latest and greatest' technology for graphics cards. It was designed to be faster, but what they really don't tell you..is that it's also cheaper and AGP can go faster if they wanted to spend the extra money
You
cannot plug in an expansion card (video card/sound card/network card/etc etc) into anything other then it's designed for.