2014 MBP boot problem

My maxed out 2014 MBP is not coming to life. I’m getting the startup chime, and a lightly lit black screen. Eventually the fans begin to slowly ramp up, but no Apple logo.

Just prior to this, I had a complete freeze where I needed to hard reset the machine. It booted, and got to 100% of the load bar, and hung. A subsequent hard reset bricked it.

Tried resetting NVRAM, SMC, and tried to boot into safe mode, recovery, and diagnostic modes. Also tried connecting an external display via display port, and HDMI. Don’t yet have another Mac handy to try target disk mode.

I am also not able to toggle the caps lock, and have read that may correlate with a bad motherboard? I’m getting the startup chime, and fan activity. Is this yet another GPU failure, Apple? If I hadn’t updated to 10.13.4, I could try an eGPU, but, that doesn’t seem plausible.

Thoughts?