The 970 works for encoding h.264 only. My recommendation: If you have a 7th Gen Intel CPU with iGPU or later, use that. Otherwise, sell the 970 and get one of these (in this order):
Intel Arc A310
GTX 1650
GTX 1630
Quadro P1000
Quadro T400
GTX 1050 Ti
GTX 1050
Quadro P620
Quadro P600
Quadro P400
The Intel Card has the best encoder, followed by Nvidia Turing, then Pascal. I recently sold my 970 and got a 1050 Ti for the same price. Works great with Jellyfin. If you need to tone map HDR, you probably shouldn't get anything with much lower performance than that. If it's just some UHD to HD or h.265 to h.264 for compatibility, even the P400 will work well.