My PC isn't up to running GTAV either. It won't run PS3/Xbox games (not that I've tried mind).
PC gaming. Hmm. It's a barrel of laughs. Took me all night trying to work out why I was getting kicked from BF3 after 5 mins of playing. Thought it was that nuisance timeybuster program so got to upgrading it and then later, plonking the files in manually as I was still being kicked.
More (mainly fruitless) searching and I finally found the cure: disable UPnP in the router et voila! No more kicks. Why the F do game devs leave bugs like that in their games? Then I remembered this had happened before and it was all because I'd changed ISPs and had to use a different router, which of course had UPnP enabled.
Ah, PC gaming is great when you actually get to game.