I bought portal 2 on the release day and I downloaded it straight away, when I started playing it though I heard the sound and saw the in game functions but my screen was black, only the menu came up and it let me exit the game and go to the ingame menu but not see the acctual game, I then procceeded to try it on multi player and then same thing happened... But I could see the Ingame chat aswell and I was talking with the other player, anything I can do (at the moment I think my drivers are fully updated, I doubt they would put another update up for them anyways its quite old.. Im going to try updating everything, ill post up later how it went.. any other suggestions (Besides "Get a new computer or graphics card" obviously 
Ps- I will be getting a new graphics card soon so it may just be that

Ps- I will be getting a new graphics card soon so it may just be that