Re: However
If he's testing alternative operating systems, that's hardly Huawei's problem. And of course running an emulator in Windows will be slower. He may as well criticise the hardware for not running Apple macOS.
It would have been more informative to report on the transcode time after booting with a Linux USB stick and using Handbrake.
Regardless, it looks like linux may be thermally throttling the CPU by default, see https://bbs.archlinux.org/viewtopic.php?id=272947
Biting the hand that feeds IT
