Quiet Slim PC Build - which PSU and CPU Cooler?

[chromwolf]

I'm putting together a Mini-ITX build for audio recording and editing, so it needs to be as quiet as possible. I've read that one of the best ways to reduce noise is to reduce heat and therefore cooling, and so I've tried to set the build up to that end, but I've got a few questions on build choice. The parts most relevant for noise and cooling:

CASE: Node 202 for the slimness, will be vertical.
CPU: Ryzen 5 2400G; Vega RX11 video is more than enough for my needs, and it's only 65W.
DRIVE: SSD, ideally M.2.

I can list other part picks if it's helpful.

Because I'm going with the APU, the GPU section of the case will be empty. I'd thought about doing AIO water cooling using Bitwit's case mod, but if air cooling would be better, I'm not married to the AIO. I think I want a better PSU (in terms of noise output and thermal management) than the 450W that comes with the Node 202, but I'm not sure which.

My questions:

1. Which solution for CPU (and therefore case) cooling should I go with--AIO, or will the motherboard heat up the CPU section of the case? Related questions:

• 
  ■ Even if I go with an AIO, can/should I worry about a fan above the CPU mounted to the chassis?
  ■ If I go AIO, should I go 120 or 240mm radiator?
  ■ If I need any case fans (120mm I imagine), how many and facing inward or outward?
  ■ If I go with AIO do I need to worry about positive/negative pressure?

2. Which PSU should I go with? I'd found out a few SFX PSUs that rank well for noise reduction (be quiet! SFX L 500W, Corsair SF450 or SF600), but I'd love to get further input.

• 
  ■ I was using the Cooler Master PSU calculator, does it (or any others) take into account the power needs of the APU, or do I need to include an RX Vega card that isn't actually there to correctly calculate?

 

[Eximo]

1a) VRM temperatures are a concern. If you have airflow through the case it should be enough without a direct fan blowing on it. But it won't hurt.
1b) 240mm is going to have more surface area so you should be able get away with lowering the pump/fan speeds.
1c/d) Depends on the overall setup. If you go with positive pressure you will want more intakes than exhaust. You would want the intakes to be filtered. If you go with negative pressures then you want more exhausts than intake. Dust will accumulate wherever the air can get in, which won't always be easy to reach places.

2) All of those options seem fine. Gold rating is more efficient and should be quieter as a result.
Even the 450W is enough to power an overclocked 2400G. I wouldn't worry about it.