Hello,i have a asus m4a785td-v evo mb, it has ati 785 chipset which says it will crossfife x with hd4650, hd4550, or hd4350. i bought a 4650 for combined performance but i can only get the onboard gpu to be recognized or the discreet, not both. it sees both but one is always disabled???
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You should disable the onboard GPU in your Hardware manager and then restart. See if that works for you.
That is what i have ended up doing. Disabling the onboard gpu and only using the 4650. Its just disappointing, i bought that mb for the crossfire feature, if I knew it wasn't going to work i would have waited and bought a better card than a 4650.