The 120GB/s memory bandwidth of the unified memory helps especially with video, I guess. The M4 CPU isn't really stressed out most of the time. Only multicam and HLG conversations it maxes out.

Once I patched my old Dell T1650 BIOS for ReBAR support yet the iGPU of the i5 1135-g7 had similar GPU performance for video as the Intel Arc A380 in the desktop PC. The old PCIe3 speed limited its performance. I heard others reported a smoother replay experience with Apple silicon compared to even a RTX4090.

I get some delays when fast scrubbing through a 9 multicam 720p timeline and just 360p proxies. Still impressed compared to what I was used to. Video editors may be surprised about the performance for the price.

How did you patch the Dell T1650 BIOS for ReBAR support?

There is a Github project [1] which has detailed instructions. The ancient i5-3570 only allowed 2GB ReBAR, BTW. GPU-Z says ReBAR / 4G is activated and working, Intel Arc Driver does not see it but seems to use it. Some part of the BIOS had to be manually fixed, AFAIR.

The PC was given for free, the CPU €11 yet overall I wouldn't recommend the process just for the result. It's only little benefit, if at all, though fun. On that occasion I also added some NVMe driver which works well, demonstrated for the similar Dell Optiplex [2][3]..

[1] https://github.com/xcuri0/rebaruefi

[2] https://www.tachytelic.net/2021/12/dell-optiplex-7010-pcie-n...

[3] https://github.com/jrdoughty/Dell-7010-rebar-guide

Edit: some wording

4x vs. the old i5, not the M4. They are trying to say that comparing to a CPU released four years ago is pointless because the newer CPU is obviously much better.