I don't think it's the scheduler this time with a single CCD, but there is significant difference. These tests focus on compute and productivity with almost no games, so most of the difference could come from this bias. Another possible option is the power profile (EPP balance_performance) holding back the 7700x on linux.
The draft is pretty good. Only a few points to consider changing:
That's a very old video format, which is definitely not HDR.
Some GPUs support the MPEG4 codec maybe try updating the driver. Did you try turning on or off Hardware acceleration for the transcodig?
Navigate to a problematic movie or episode -> 3 dots -> Get info -> right column -> Color space
Usually SDR is bt709 and HDR is bt2020. In older codecs (h264) 10 or 12 bit color depth can also cause issues.
I'm not sure how tone mapping works on plex since I don't have a pass but with Jellyfin you need to setup OpenCL which is run on the GPU so your guess that a hardware change can break it is plausible.
green tinge to them
Are you sure it's corrupted and not an unsupported HDR color format?
Corrupted files usually skip frames or get blocking and ghosting errors.
That's more than enough. You can't do any more.
As an Android flavour it should be safe after uninstalling all apps associated with the university. Did any of them need a "device owner" permission? That's the only way to be more persistent on Android without root access.
The mobile and TV clients are often limited to the codecs with hardware acceleration. Or just selecting a lower bitrate on the client will cause transcoding.
The FS feature is great, it's just cumbersome to use without a tool.
Snapper works well for a local backup like history both against botched updates and accidental deletion, but eats up the free space with the default settings.
Timeshift is an easy to use GUI but doesn't support non-default partitions.
Also the quota support had a nasty side effect: freezing the whole system on snapshot deletion.
I think calling it a "cache" is not precise. The primary function of the DRAM is to hold the dictionary for translating logical addresses (e.g. sectors) from the OS to the physical addresses (which NAND chip, which bank etc.). This indirection is needed for the controller to do wear leveling without corrupting the filesystem.
On a SATA SSD without DRAM each read IO could mean 2 actual reads: first the dictionary to find the data and than the actual data being read. As you said HBM helps by eliminating this extra read.
The read and write caching is just a use of the remaining DRAM capacity. Since modern Operating Systems use the general RAM for the same function it is usually just a small increase to the throughput.
if the integrated one is good enough for gaming
No, the iGPU is only meant for testing and basic desktop usage like video playback on the 7000 series. There are 8000G series with better integrated graphics but even those are much weaker than any dedicated GPU.
That ATX board would be great. The mATX B650M PG is also better than the previous one, it is good enough. If you can find the B650M-HDV/M.2 in stock that is even better if you don't need 3 m.2 slots.
That monitor was indeed a lucky deal. It looks to be a good combination for this setup.