My Dell 4K monitor was not getting a signal from my ASUS NVIDIA 750 ti graphics card.
Wound up buying a dual link HDMI (f) to DVI (m) adapter ($5 at Fry's) and works great.
3480 x 2160 resolution at 60hz
Not sure the HDMI port on the graphics card ever worked. Had been using the VGA port and the HDMI from the built in graphics on my motherboard for a dual monitor set up. The built in board (Intel HD graphics 530) would drive the 4K monitor but only at 30 hz.
windows 10
8 gb DDR 3 memory
ASUS mobo
ASUS GeForce 750Ti graphics card
Intel i5-6500 CPU
Dell U2720Q 4K monitor. Comes with both HDMI and Display port cables
