I've had numerous builds in the A4 cases over the years,
My current build being:
A4 V4.1
R5 7600 with Thermalright AXP9-47
32GB Corsair 6000mhz CL36 DDR5 (stuff isnt on the mobo QVL, and cant get it above 5600mhz, but was the cheapest kit i could get)
MSI B650i Edge
Inno3D 4070 X2
Corsair SF750 (Thought my SF600 had died and got this one cheap)
Custom PSlate Cables (actually the cables from my old FormD T1 build, but work near perfect in the A4 aswell)
I built this system when my wifes trusty R5 2600, 1080ti, A4 V3.1 builds mobo died, and i wanted to play BG3, so was all a bit of a rush build.
My experience with multiple systems in A4's over the years, including a 3950x under the C7G (eco mode) is that the A4 is still the best case ever made, and the hardware limitations it presents generally dont matter for the majority of users.
they do run hot, and they can be loud, you just need to find teh balance of temp and noise you are comfortable with.
Some of the tricks i used in older A4 revisions was noctua 40x10 fans to get air moving, especially behind the motherboard, so i ran the riser cable on gpu side so i could pump air down the back of the motherboard to cool my secondary NVME, this worked wonders, newer revisions have the space for a 92mm fan under the board (noctua slim only i think?)
the other thing is, the case itself works are a really good heatsink for components, so don't get too worried if the chassis is hot to touch, as long as component temps are in check, ive even used a small usb fan at low rpm to cool the chassis before, worked well.
As for parts selection.
Whilst the 5800x3d is still a stellar cpu, seems unless budget is a real concern, that sticking to Am4 when we are already a decent way into Am5 life is a bit silly, especially when Am4 ITX board availability is pretty poor, and I've had the highest failure rate of motherboards in my entire computing career with am4 ITX (though my B350 asrock Fatal1ty board just keeps on going witha 2200g. . . )
I guess what I am saying here is, AM5 may be a better path for future upgrades, and support life etc, but it will come at a decent % increase in cost over Am4.
just don't get the MSI B650i Edge like i did, the ram support seems poor, and the bios is woeful, its my first MSI board since Pentium 4 days when Red PCB's were a thing. . . . it will probably be my last. (was the cheapest am5 itx board i could get locally)
For GPU, ive got the X2 version of the Inno3D 4070, its not loud in my opinion, but bigger cooler and more fans to spin at lower rpm 'should' be quieter. we only have the 4070ti in the X3 model in Australia though i think.
my 2C anyway.
