Tautedorus

@Juular, I recently stumbled upon Deepcool power supply product page again and noticed that they've changed the internals of the DP-BZ-DA600N unit. It seems that the platform shown in the picture (links are in the quoted post) doesn't use DC-DC regulation. If you can recall, this was not the case earlier. Because of these changes, I guess we cannot really trust Deepcool with their DA-N line of products and we need to move them to a lower tier alongside the other low-end Deepcool units (DA, DA-M, DN, etc.)

I had the same problem when I bought my Ryzen 5 3600 (technically still have). Unfortunately, I've tried all the things mentioned above to no avail. In the end decided to slap a beefy cooler on top of it and call it a day.
 
You can try undervolting it but I really doubt you will be able to do it without a significant performance loss (especially single-core performance) and stability issues.

Sorry, still doesn't make sense. Do you think that because the unit has 80+ Bronze rating it outputs less power than it's rated for or what ? Because that's not how it works, as Tautedorus already said. Efficiency is what PSU draws from the outlet after what it provides the power for the PC, if it's rated for 480W at full load then it provides these 480W (even more actually, before it shuts down, because all PSUs have some overhead), and then the efficiency factor applies so it draws like 550-570W from the outlet. In the end, 80+ badge means absolutely nothing but how efficient the PSU is, it's not a matter of components quality or performance or it's capability of outputting power in relation of what it's already rated for.

Depends on the exact PSU model (and other parts of course). Remember, higher wattage ≠ better quality.

Depends on the exact PSU model (and other parts of course). Remember, higher wattage ≠ better quality.

That is probably a newer model of Deepcool DA series power supplies, which has a DC-DC regulation (internals).
 
Considering that at this moment it's pretty much impossible to build a PC with a solid discrete GPU at a reasonable price, I should just go for it. Compared to many other pre-built PCs in our country, the PSU is pretty decent and will probably work just fine. Though, I suggest replacing it after the warranty expires.

If you gonna power something that needs 750W, you should buy a quality power supply unit. And those units, as you said, usually cost more.

If you don't install or give admin permissions to random stuff that you find online, you don't need anything more than a Microsoft Defender.

Shrek makes up for other 350W.

Ryzen 5600X has more or less the same power consumption, so wattage wise you'll be fine. However, we don't know if your PSU is a good quality one. If it's a poor quality unit, maybe it's a good idea to upgrade alongside the CPU. So, it would be better if you include the PSU model as well, not only the wattage. And yes, you will need a motherboard upgrade because B350 chipset motherboards won't support the new Ryzen 5000 series processors.

I would say, maybe use it until the next upgrade or until the unit starts acting weird.

The 24 pin ATX connector looks the same an all modern PSUs, nothing to worry about here. But if your PSU is poor quality, that's another problem.

Yes, this is normal. It was meant for a now deprecated -5V rail wire.

All of the questions that you have will probably be answered by reading this article by JonnyGURU or by watching this video where he answers most common questions and debunks misconceptions about multi-rail PSUs:
 

All of the questions that you have will probably be answered by reading this article by JonnyGURU or by watching this video where he answers most common questions and debunks misconceptions about multi-rail PSUs:
 

All of the questions that you have will probably be answered by reading this article by JonnyGURU or by watching this video where he answers most common questions and debunks misconceptions about multi-rail PSUs:
 

https://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=1648620
 
This is the closest thing I can come up so far that semi matches your description (that I can glean) sans the brown sound dampening material (obviously this one has a plexy panel)
 
But those power and reset buttons match like a boss
 
 
 
 

@Juular, also in the units index Xilence Performance A+ III should be labeled as a semi-modular unit. By the way, are there any plans to add SilentiumPC's units to the index?

It's old.
Corrected.

I was looking through the units in the units index spreadsheet and noticed a few errors:
Deepcool DA-N 500/600W models are labeled as group regulated units and the 700W one as DC-DC. This needs to be other way around. We discussed earlier that new DA-N series unit have DC-DC regulation and the 700W unit is still group regulated. Seasonic Focus GX is labeled as a semi-modular unit. This needs to be changed to fully modular and Seasonic Focus GM needs to be added and labeled as a semi-modular unit.

I live in Lithuania too. Here's my suggested part list from our local shop Skytech:
 

Here to solve the mystery for you guys.  The 275R has a similar chassis design to our SPEC-06 which has an RGB variant.  The hole is for the controller that allows adjustment of the front RGB.

The CV 650W is DC-DC on the secondary. Do you not bother doing even basic research? Cybenetics did testing for it.
https://www.cybenetics.com/index.php?option=database&params=1,0,28

 
Jonnyguru was talking about the lower wattage CV models, which are group regulated. The 650W is not.
From the same Cybenetics report:

Well, this is just asking for trouble. Molex cable has just one 12V wire whereas 8-pin PCIe connector needs three. I strongly recommend against using that adapter.
 
Rule of thumb: if your PSU doesn't have enough cables, it's not meant to power your system. You should get a new good quality unit.