I have a Gentoo Linux Box connected to the HDMI input of a Yamaha stereo receiver which drives a Samsung Flat Panel LCD.

I used to have a GeForce GTX 750ti connected and it worked mostly, except every once in a while when I would turn on the receiver and the TV, the screen (even though locked in 1080p (or sometimes 1080i) no pixels would show up. Even if I hit CTRL-ALT-F1 and switched to a console, I never got pixels. The only way to get around this was to restart sddm which would bring back the display.

The Geforce GTX 750 ti died last week and I removed it switching back to my motherboard intel 915 drivers connected exactly the same way.

Now, every time I power off the receiver and the TV, I lose video and restarting sddm does not fix the issue. In fact, rebooting didn't fix the issue I had to reboot and power cycle the receiver and TV to get the screen back on.

This is problematic as my family depends on this PC for various features, ie Netflix, etc. And the server run security cameras and mythtv backend as well as running a RAID6 array with all my data. Rebooting it daily is not an option.

I didn't have this problem until I switched to plasma, and it happened with the nvidia drivers, so I'm thinking it could be a software issue with plasma, KDE, or XORG, but honestly it could just be a coincidence. I have updated kernels, drivers and other things since this issue started.

Is there a way to debug this? Can someone give me some pointers on where to dig around to get some idea of what may be happening?

Thanks.