Why does my Onboard graphics controller work better than my ATI radeon 7000?

Question

So i recently bought an ATI video card for my dell. i installed it.

when i tried to play my favorite game. it lags sooooooo much. but when i use the onboard the game works smooth with no problems...

why is that?

Oh and my PC is a Dell optiplex GX270

Answer 1

try getting the latest drivers your card

Answer 2

My guess would be that you are using the Windows drivers to run your new video card.  Common mistake.  Go to ATI's website and make sure you not only have the most current driver, but all of the updates to it as well.

Also, you will want to disable the old video driver by going to the System section of the Control Panel and clicking on Device Manager.