You sure can. It will not get the hardware acceleration from the main card, but it will still work.
Strangely if you drag a windowed game over, it will work much better then onboard alone(but not fast as dedicated alone)
nukemaster-thanks, is there any driver that i need to install to make this work? When I plug in my 3rd monitor (vga) to the onboard video, nothing show up. I enable the onboard graphic settting in bios and boot into my win 7. Is there anything missing to make my 3rd monitor work? Again thanks!
Intel has drivers for it and you have to ensure that the bios is set to allow multi monitor or similar.
If it is not set right, the onboard video will be disabled when the dedicated is detected.
You should be able to see them both in the device manager.
THANK YOU NUKEMASTER! I got this to work! also, btw, for some reason, my video now runs better getting around 50 fps on black ops 2. so not sure if this mean crossfire, prob not, but am curious if it actually improve graphic performance?
fyi - after setting up the 3 montior to work, i used the mis after burner to overlcok my ati hd 4890 with 930 core clock and 1000 memeory clock. when i loaded black ops, it was display on my main screen which is from the 4890 dvi.