1st - some random PCI 2-4MB card
2nd -Trident PCI card maybe 4MB
3rd - ATI AGP Rage pro 32MB (something like that)
4th - integrated and PCI 32MB card dual monitor
5th - integrated 64-128MB shared (current notebook)
6th - nVidia FX5200 AGP 128MB and Matrox PCI tri monitor (current desktop)
7th - soon to get a GeForce 7600GT for a PC that is running on integrated for now (will be dual monitor)
Note that these were all on different PCs, and not just upgrades. Some systems I didn't use very long because I was given something better, but this is the main idea from the main PCs I've used.