I built this for gaming as I didn't want a next-gen console. It has worked really well, I have AC IV and it runs well (no clue what frame rates I get but I don't notice any stutter). I can run Skyrim with quite a few mods including an ENB. No issues with anything. Everything runs well, definitely would recommend to anyone on this kind of budget. I haven't got the keyboard yet though. I'm using dual monitors, a 19" 1366x768 and a 23" 1680x1050 (I know, weird resolutions).
Cost was £545 (at time of purchase) for everything below (except the mouse) + my 19" monitor. (The mouse and second monitor were gifts)
Just seen the current price, brilliant price haha, if I got it for that I could've gotten myself a better monitor.
If anyone has any recommended upgrades please tell me.