Win 10 /// RTX 2080 Ti Strix OC 11Gb (water cooled) / Ryzen 3970x / 128 RAM / m.2 970 Evo Plus SSD
Test file 0,5sec 1080p 30fps x2 interpolation (15 frames into 29). 15 frames original from the video. This means that only 14 new frames was generated.
Split frame into section setting:
@ 850x150 - 3m:03s ~ 12 frames rendered about 2m:37s
@ 700x150 - 3m:26s ~ 12 frames rendered about 2m:56s
Even if calculate the processing of all 29 frames during interpolation, your PC configuration completed this task faster.
Maybe it depends on the content in the image? Otherwise, I don’t understand why my computer rendered frames much slower than yours ...