Somewhere around 35 watts maximum. It can handle multiple 1080p streams, but only one 4K stream, and the limitation is due to the 2GB of RAM on the card.

I have a very low-use server, so the card is perfect for my needs.

My current build is a small quad-core Xeon from the Haswell era and does just fine. I added a Quadro P400 for PLEX transcoding. If the rig also did storage, it would also be fine. You’d be good if you wanted to add a Quadro card to yours.