how can i fix my portal 2?

[dr244]

I recently bought and downloaded Portal 2 from steam but when i load a new game its just a black screen. after the menu and loading screen (which I can see fine!) i can see the cross-hair and the "please press w,a,s,d" thing but the rest is just a black screen...Does anyone know how to fix this? seriously guys, any help at all would be appreciated. I just really want to play portal! :'(

[JSIMMO]

Change the games display settings, you should be able able to do this through steam, start from the lowest possible graphics and work your way up :)