I know this thread is dormant now, but I am just getting a Realan e-W80 case ready for an ASrock ITX MB ( with Samsung 960 EVO M.2 256GB) and a Raven Ridge APU when they arrive..............
A couple of points that have been mentioned here:
Power........I removed the stock power board...........messy cables and I never quite trust the power solutions that come standard, will certainly not be chosen for "best in class".........I will be using a G-Unique Archdaemon Limited Edition 300 watt...........Probably overkill for an APU system, but neat, silent and cool and I am happy that the quality is up there with the best...Plus, there is a rumour that there may be a Dragon Slayer Raven Ridge at 95w-TDP, in which case the 300w will be justified.
A Bonus to removing the stock power board is the space created....and the mounting points thus freed up. This has enabled a 3D printed SSD holder to be mounted in its place. Lots of airflow round it and easy access. Lpus this releases the SSD carrier plate which I feel reduces airflow anyway.
Cooling/venting:
I too have run an ASrock A88x ITX motherboard with an A8-7600 in this case, and I agree, it gets hottter than desired......I used an underslung fan Kotuzi, ( or is it Kodati? can never remember which is which)
I did use a 50mm fan in the inbuilt mount for the side vents, a 50mm Gelid which was very quiet and may or may not have been useful. Hard to tell.
One way I do deal with in this style case is very simple: Remove the lid, fit MB standoffs in place of lid screws ( 6/32 thread) replace lid using original screws........In my case ( pun........) I now have a 4.5mm gap/vent around top of case...........
Unsure what CPU cooler I will be using, probably a Silvretta or Cryorig C7 and Noctua 1600PWM Redux on whichever heatsink I use.
There is one other issue, brought about by using the G-Unique......The one I have uses the 8 pin block connector and this case does not have anywhere suitable to make such a hole as would be needed, nor would I want to hack this particular case.
The solution I am trying is this: The AB350 and X370 from ASrock (ITX) both have the same I/O layout, with an unused space above the 2x HDMI ports........Behind on HDMI is the 8 pin CPU power, so space a bit restricted, behind the other HDMI is the infamous VRM heatsink..... jus enough room for what I have in mind.........A £D printed I/O plate with a mounting for the 8 pin power connector above the HDMI port in front of the VRMs.............All worked out and fits.
Why am I bothering? Because I like this case, and I like tinkering with ITX!