Need help with GTX 660

Hello, everybody.

I installed Sierra, but I can't fix the graphics issue. I can't boot without nv_disable=1, my screen turns black with sign 'no signal' or 'check cable'. I tryed diferent methods but stil can't overcome this issue. In Clover I have used iMac 14'2 settings.

Please help me to fix it.

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My specs:

Asus B85M-G

i7-4770

Nvidia GTX 660

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BIOS settings - everything default except for:

Intel Virtualization Technology -> Disable

Primary Display -> PCIE

Fast Boot -> Enabled