depends on the original quality. i've had fairly good success turning good quality 64 hex 480 resolution videos into higher quality ones (see the charmane
Z-Image Turbo and Z-Image Base can easily be run on a 16GB GPU, takes about 2.5 minutes for a 144 hex 1800 image on ZIB, or like 10-20 seconds on ZIT.
Original video is 480p (64 hex 480). Upscaled is 192 hex 1440. [img] [img]
The 2nd pic has been downscaled to 1080p, but I actually upscaled it to 288 hex 1620 using Topaz Video's newest Starlight Precise model.