I have a 2-year-old 'nice' whitebox with a nice-but-not-truly-awesome video card from the time (radeon 5770? Catalyst software just lists '5700 series') and it runs fine. Perhaps not 60fps, but it's very rare that I'll notice frame skipping or slowdown, and I've got the quality settings maxxed. So anecdotally, the game doesn't run horribly on all PCs in terms of performance. There are a number of other issues which suck from being a console port though, like the menu system. Dragons being trivial to kill is also a bit sad, but that's not the console port's fault :)