It should switch over automatically I would guess. Mine does, but I can set it manually too if I want to make sure or to make it use the APU's graphics chip instead. If you want to make sure it's using the 7670M discrete card, download and run the AMD System Monitor software to check. It's here....
http://sites.amd.com/us/game/downloads/ ... rview.aspxJust click on the details buttons of both the APU and 7670M in the program to get it to graph it. Also stretch the window of it across the screen a bit so you get a nice long graph of it's usage. Play the game a bit and then exit out to windows as quickly as possible so you can see if the graph shows the 7670M getting used.
Just remember to stick with your laptop maker's drivers for your model. I learned that the hard way as this thread I made of my journey into learning that and it's problems is here.....
viewtopic.php?f=33&t=6740If you have an HP, you should be able to set the power mode which in turn decides which GPU is to be used. It also allows you to enable Crossfire mode. I think there is a profile for COD 3. You should have better results then me in crossfire mode (see my sig for my specs) cuz your APU's GPU and your discrete GPU are closer in power to each other then mine. That helps a lot more when it comes to load balancing issues and the reduction of micro stuttering.
Hope that all helps!
