Vista - Can't Play 3D Games.

I have this Dell Inspiron 531S that we got last year which worked fine with games of any kind. (Age of Empires 3, GTA SA, Spore, etc..) It work wonders for 5 Months untill my parents thought it would be best to get a new Computer Desk. (Our's was just a regular desk that holds both the PC and the Monitor on top of it.) This new one is about same instead that it has a cabinet on bottom that puts the PC in with opening at the back of it. (Cords, etc.) Well, my first time trying it. I started to play some CD Games (Manily 3D ones.) And I notice that when putting it in driver, it will harly respound and that it seems the Fan that would run when a game starts will also not respound. (This will also effect any 2D games CD's.) It will put up the install menu, that is all. But if you try to play the game, the game will ( I think its on Lock Up.) freeze the entire computer (Including my mouse pointer.) to where that I would have to restart the whole computer. (Game will not show up and it will freeze me on my desktop without starting the game.) I did a test on the drivers and detected no problem from it. I am thinking it had to do with my new computer desk (We had to also disconect the whole computer just to put it on our new computer desk.) What I also found out that when I booted up the computer. The blue power button will go orange for a few seconds until it goes back to blue. (I know what a orange light means.) So yea, Help?

Try reinstalling all your drivers and see if that helps, also check that all the leads are firmly in the back of the computer.