HTPC not displaying through Receiver

I recently bought a Harmon Kardon AVR1510S for my home theater system to handle my HTPC, an Xbox One S, and an Apple TV. The HTPC I have is using a GTX 750 (I've also tried a GTX 660Ti SC, both cards are tested and working in normal environments) and is hooked to the AVR via a brand new HDMI cable (switched cables just in case).

The Apple TV and Xbox display just fine and sound quality is excellent, however when switched to the HTPC, the AVR does not play any sound or display anything on the TV. The TV does say that the receiver is connected, but that "there is no video signal".

I've attempted changing the framerate from 60Hz, to 59Hz, to 30Hz, to 29Hz, but none of these options regained a video signal. Changing the resolution from 4K to 1080p or even 720p did not work either. I also used DevCon to set a hotkey to reset the GPU in an attempt to regain any lost or invalid EDID in the HDMI connection, but this did not correct the issue. All of these options have been tried with the GTX 750 and the GTX 660ti with fully updated and even re-installed-from-scratch drivers without any results. The HTPC is running Windows 10 if that matters and I have even re-installed Windows in an attempt to correct the issue, but this did not modify the result.

I talked to a Harmon Kardon technician for a couple hours on the phone troubleshooting various things, but in the end the tech had to open a case and escalate the issue. I have not heard back in 4 days.

My laptop (GTX 960, updated drivers) is able to hook up to the same HDMI connection and successfully display through the AVR to the TV, but only after resetting the GPU with DevCon the same way I was attempting to on the HTPC, and only if the screen from the laptop is "mirrored"; "Extending" the display reverts to the same loss of signal as before.

I've attempted switching the input port on the receiver, as well as the output HDMI port (there are 2) on the graphics cards, but still no dice were had.

Has anyone here experienced a similar issue with HDMI connections through a receiver and/or know of any troubleshooting methods I've yet to try?

Submitted by Xsurv1veX | #Specialdealer Special Offer Online Shopping Store 2016