I got steam a few weeks ago,and then got TF2 for free.Then after i downloaded it,It started to freeze my computer.It made me lag worse,like on SWBF2,and TF2.
Steam is very annoying to me. Hogging my PC's CPU. Lagging all my games because of that. Crashes when ever I download a game. Always asks me stupid questions. Like, Are you sure you want to exit? Duh why else would I have clicked on it! Those get too me. Too bad you can't play tf2 or maybe you can try to lower your game resolution and other settings. They might be too high.