I have an HP ENVY TouchSmart 4-1215dx Ultrabook Laptop running Windows 8.1. All hardware is standard except I upgraded the 4GB of RAM to 8GB. Up until recently (2-3 days ago), I have had no issues connecting my laptop to external monitors via HDMI (no VGA).
Now, however, every time I connect anything to my HDMI port it simply does nothing. It doesn't detect or show the additional display when in
Right-click Desktop > Screen Resolution. Also, when my monitor is just sitting without any input, it says
No DVI-D Cable. The display will go into Power Save Mode in 5 minutes. When I plug in my laptop, the monitor immediately goes to sleep.
I don't know of an event that would have caused a change in functionality. The only thing that seemed to somewhat coincide with this is my OS recently (yesterday) got removed from the BCD and I had to rebuild the BCD from the system recovery command line tool in order to get it to boot.
I have tried rebooting, reconnecting the monitor, and plugging in the monitor before I start up my laptop. I also tried re-installing the Video Driver using the HP-provided drivers here
Any ideas where else to look or what else to do? I have looked around and haven't been able to find any leads. My only thought is that it's a hardware problem and I somehow messed up my HDMI port. Thoughts?