Does Handbrake use GPU acceleration?
HandBrake is very CPU intensive. It supports hardware accelerated encoding, which is only for video encoding, and is not used for video decoding, filters, audio encoding, muxing and audio/video sync. So the CPU usage of HandBrake is usually high (even as high as 99%). Here's how you can enable GPU acceleration on HandBrake: Go to the menu bar > select Tools > Preferences > Video > see the supported and available hardware encoder.