The very first "upgrade" I did on my very first PC was a video card, and I ended up buying the GeForce 4 MX440 SE (yeah, the Sucky Edition), the PCI one of course. I bought that because the first "3D" PC game I ended up buying (before Diablo II) was S.W.A.T. 3, I was told I had to get a graphics card, so yeah. I knew absolutely zero about computers so I just went to my local Future Shop, asked the clerk for a video card around the budget I had (not much, I can't recall how much I had, around $80 I think) and he pretty much just took that box and said that I should go with it, and I did. That was back around summer 2001 if I recall correctly.
I die a little inside every time I think about that.