It is wierd, yes I have friends that have successfully have gotten there 7750 to work with there onboard in a Dual Graphic setup.
The 7750 is about twice my onboard 7660D, but I went with a 7850 so not to have the mess of Dual Graphics. It is also a hit and miss as to being dependable or not. Some people get really crappy performance while other it works great.
What type of games are you trying to play? The CCC 3Dgame App settings can be tweaked a little to get some pretty good FPS.
Here is what I use compare it to what you have.
Now my CCC settings are:
-- Anti-Aliasing --
Anti-Aliasing Mode & Samples are Use app settings
Filter is Std
Anti-Aliasing Method is Multisampling
Morp Filter is Off
-- Texture Filtering --
Anisotropic Filtering Mode & Level are Use app settings
Texture Filter Quality is Std
Surface Format Opt is Off
-- Frame Rate Control --
Wait for Vertical Refresh is Off, unless app specifies
-- Tessellation --
Tess Mode is Use app settings
Max Tess Lev is Use app settings
AMD A10-5800K, XFX 7850 Ultra OC Edition 975MHz, 16GB RAM, Win 8.1 Pro 64 bit, MSI 7778 motherboard, 500W PSU, HP P7-1235, CCC 13.12 WHQL
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