VIDEO CARDs, which use for test:
GIGABYTE N75TWF2BK-2GI
SAPPHIRE HD 5750 VAPOR‑X
Please see, how convert this video
by x‑video-converter-ultimate6-uk.exe Trial version program
tested by trial program : PerformanceTest
For end, NVIDIA is crazy, why ? please see this: Can’t use CUDA to convert videos anymore after 340.52 update!
1000 frames {720p} take
1:21s — by ATI R9 270 (2014)
Thats mean old one is better for renderink like new one.
If you want, make your GPU faster please use this solution