Help! Graphics card incompatible with Motherboard?  

how are you trying to connect VGA or HDMI also you might want to check if you have the VGA connected to the DVI because there not the same

Plug in your card, make sure all cables are connected(if all are connected please unplug and reseat them). Heavy graphics card required power connecters. Start up your computer go into your motherboard and disable integraded graphics save and exit. Connect your video card with DVI or VGA. I recommend VGA(older but seems to work almost all the time when DVI may not work immediatly.) if nothing displays on the screen and you have tried all connection slots(DVI/HDMI/VGA) open your computer. When you turn it on do all moving part move? Does your graphics card cpu fan move?

Can you test this graphics card in a different motherboard(computer)

do one at a time try HDMI first on HDMI 1 and just boot if there is a signal just stick to HDMI usually any newer card will input HDMI first before VGA so test one at a time and if the PC boot beep goes through and no picture Unplug it then replug it and see if it opens up

Go into your BIOS and navigate to Chipset, and select Graphics Configuration.
Select "Primary Display".
Change Auto to PEG.

Select "Internal Graphics", change Auto to Disabled.
Save the settings and turn off your computer.
Plug in your monitor cable to the GTX 660 ti.
Turn on your computer.

It may or may not work, depending upon what the problem is, but you should try it.

My Biostar Board i didn't have to do this and has a dedicated 4200 but then again you could be right not all motherboards disable onboard for dedicated good call