I have a Sapphire RX480 Nitro+ that I purchased new about 11 months ago...and it just died. It powers up with its little LED light, but no output via Display Port or HDMI. Nothing. As soon I remove the card, I'm back in business. If I put my old 7870 in here, I'm back in business. I tried changing to a BRAND NEW PSU that was much more expensive (Seasonic mid-range) and no dice again. Also, sometimes, the pc will just power off while I'm merely troubleshooting this card! Anyone else having/had a similar problem? If this card is dead, this is a first for me. 11 months? Brand new card? DOA? Pfft. I'm switiching. Period. Nvidia might be more pricey, but at least their stuff works.
Oh, and I tried removing my bios battery,etc...no dice there either.