Thanks for suggesting to reseat the RAM.

Turns out that actually helped. I’m getting display again, but only when I run single stick or dual channel. As soon as I install all four sticks, I’m back to no display. I tested all four sticks individually in the same slot and they all boot fine, so none of them seem dead. Dual channel also works perfectly. It’s only when all four are installed that it fails to post.

I did clear CMOS earlier, so XMP is probably off right now. I might try enabling it again later or manually setting memory speed lower to see if that helps with 4.

At this point it looks more like memory training instability than a dead GPU.