I am pretty sure this doesnt apply to games, because tf2 still sucks ass....but ive figured out it might be my outdated video drivers :o and i dont know how to update them D:
It does apply to games, but there are so many other things that also apply.
Download speed, processor(to a point), and depending on how crappy your connection is, the number of connections open on the router. These matter for your connection speed, which will make things seem delayed, while the screen will be working just fine. (Example, you sell an item, but it doesn't dissapear till 10 seconds later)
Processor, RAM, video card, and whether or not they're being used by other programs aswell. These control your client rendering and objects and such. If these are bad, you may still have a good connection, but the screen may look like a slideshow, or the game may even crash. If you're hosting a non-dedicated server, it may even lag the server due to your computer being busy.
