I was never lucky enough to get a decent pc when I was growing up, we had some budget pc capable of a bit of browsing and some word pressing, that was about it. Now I wouldn't bother to invest in a desktop PC to game on as I'd rather just use a console.
I used to run championship manager on my old laptop though. That game nearly destroyed a relationship I was in with an old girlfriend. I used to lay awake at like 3 in the morning thinking of transfers, strategies etc. Then I would get up and actually do them. Sitting there in the pitch black with my pink dressing gown, even the cats were getting pissed off with me. I just couldn't stop playing it though, in the end I just had to stop playing it completely, I couldn't say 'right I'll only play for an hour a day'. It was all or nothing, in the end I chose nothing.
I will never ever buy a championship manager game again for fear of what it might do to me.
I used to play Unreal Tournament with all the lads in sixth form. We used to sit in the IT room some lunchtimes and some kid would load up UT across all 18 machines. That was mental. All of you battling each other in the same room, never seen anything quite like it. Then the IT teacher would come in and blow his top that these machines were for learning and not silly games, then chuck us out.
Good times.
I hope that helps.