I just buy new things when a computer starts to die on me, replacing the entire setup. Since I don't buy graphics-intensive games typically until after they've been out a year, I tend not to notice that I'm not at the top of the hardware curve. Lara Croft's hair be damned, for right now the best I need is for Skyrim to look pretty.
That's my plan too. I'm far too cheapass to upgrade something that's just going to catch fire eventually anyway.
Maybe next time I'll get a machine that can actually play the games from 5 years ago cluttering up my Steam library..