Could not use GeForce card for cuda only and Intel Integrated graphics for display

When installing CUDA 5.5 in Windows 7 64 bit Intel i5, I enabled Intel Integrated Graphics Device (IGD) for display and GeForce GTX 560 Ti in PCIE3.0 in H61 motherboard. But installation did not detect CUDA GPUs. So I disabled IGD and installed CUDA 5.5. NVIDIA control panel displayed GPU0 as GTX 560Ti.
I again switched to IGD for display. but when I run NVIDIA control panel, it says “no CUDA capable GPUs found”. but the display adapters in device manager has both “NVIDIA GeForce GTX 560 Ti” and “Standard VGA Graphics Adapter”.

My question is “why NVIDIA GPU is not detected by NVIDIA control panel even it is displayed in device manager?”
Can I use GeForce GPU only for CUDA computation without using it as display in Windows? I know that I can use it Linux. Why not in Windows?
Also during installation why does it not detect GeForce GPU which is not connected to Display?
What am I doing wrong?

Edit:
I enabled ASPM in BIOS settings. Now NVIDIA control panel give error “You are not connected to a display attached to an NVIDIA GPU”. How to use it for CUDA?

I have same problem with four GTX 1080 and Intel HD 4600 adapters on Windows 7 x64 Pro.

IGD is required be enabled in our servers to access it via KVM.

There are GTX 1080 and Intel HD 4600 devices in Windows Device Manager and they all are enabled. But there is no CUDA device detected.

Is there any software method to make GTX 1080 adapters accessible to CUDA without physically attach display to it?

You don’t have to have a display attached to a GPU in order for it to be usable in windows, or detected as a CUDA device.

You have some other problem. It may be a problem with your motherboard, or motherboard compatibility with 4 GPUs, or simply that you have not installed CUDA correctly.