HeLiOn

The Memory Context Restore setting was on auto. I switched it to On, and it significantly reduced the training time to around 5 seconds.
Thank you.

I never considered that, thanks.
Although, I don't think it will be necessary with the Vengeance kit, cause they're really low in profile.
Just checked, and as you suggested, it's "AMD EXPO Profile Ready"
I also found the Deepcool AK620 to be available, so out with the Noctua.
Everything is now lowered to 878.14 EUR

I'd mark both of you the rep, if I could.
Thanks a lot for the help. If all goes well, I'll be putting this thing together myself in 3 weeks.

I never considered that, thanks.
Although, I don't think it will be necessary with the Vengeance kit, cause they're really low in profile.
Just checked, and as you suggested, it's "AMD EXPO Profile Ready"
I also found the Deepcool AK620 to be available, so out with the Noctua.
Everything is now lowered to 878.14 EUR

I'd mark both of you the rep, if I could.
Thanks a lot for the help. If all goes well, I'll be putting this thing together myself in 3 weeks.

Again, NH-D15 is overpriced for the current market, if you can get any thermalright coolers theyre much better bang for buck, if you cant check out the AK/AG620 from deepcool, very similar cooler to both of the aforementioned ones and again half the price of the noctua for the same performance

Thank you for the help. So for now I have:

TUF B650-Plus - 202 EUR
Corsair Vengeance 32GB DDR5 6400MHz - 151 EUR
AMD Ryzen 7 7800X3D - 454.06 EUR
Noctua NH-D15 - 103 EUR
It all sums up to around 915 EUR, which is well below the intended budget of around 1200 EUR.

Thanks a lot for your suggestions.
Maybe can find the cooler you mentioned, and save even more, but the chances are slim. It doesn't seem to be sold in my region at all.

Update:
I tried connecting using Edge, and it worked. I successfully accessed the cockpit control panel.
The 2159 error is only caused when I try logging in using Opera... which kinda sucks, cause it's my browser of choice.
 
I'll mark this one solved, for now. Thank you for your assistance, @Master Disaster!

You got that one wrong.
It's not 1 GB of RAM for every TB. It's 1 GB of RAM for every hard drive used.
You can read the detailed requirements here. Basically, the minimum amount of RAM required is 8 GBs.
It will probably need more if you use more hard drives and you plan to install virtual machines or several additional plugins.

After further testing, I came to the conclusion that the switch was being weird. 
I had to manually set the connection to 100 MF on the switch for TV to negotiate properly, but even after that, the download remained below 10 Mbps, while upload reached around 80 Mbps.
Eventually, I decided to reset the switch to its factory settings. After setting it up again, all the devices, including the TV negotiated properly.
Now the TV seems to get the intended speeds. Both Plex and Netflix are working fine.
And after upgrading its Ethernet drivers, the secondary PC also reaches the desired speeds.

So... problems solved, I guess.

After further testing, I came to the conclusion that the switch was being weird. 
I had to manually set the connection to 100 MF on the switch for TV to negotiate properly, but even after that, the download remained below 10 Mbps, while upload reached around 80 Mbps.
Eventually, I decided to reset the switch to its factory settings. After setting it up again, all the devices, including the TV negotiated properly.
Now the TV seems to get the intended speeds. Both Plex and Netflix are working fine.
And after upgrading its Ethernet drivers, the secondary PC also reaches the desired speeds.

So... problems solved, I guess.

After further testing, I came to the conclusion that the switch was being weird. 
I had to manually set the connection to 100 MF on the switch for TV to negotiate properly, but even after that, the download remained below 10 Mbps, while upload reached around 80 Mbps.
Eventually, I decided to reset the switch to its factory settings. After setting it up again, all the devices, including the TV negotiated properly.
Now the TV seems to get the intended speeds. Both Plex and Netflix are working fine.
And after upgrading its Ethernet drivers, the secondary PC also reaches the desired speeds.

So... problems solved, I guess.

Thanks guys. Turning game mode on, solved the lag issue. It behaves like a normal monitor now. 
I wanted to get the C9 myself but they stopped manufacturing them and we ran out of stock. Got this one after carefully looking at the specs.
Thank you for the advice, I'll try it out.

Thank you, I'm going for it. It should arrive Monday, if everything goes well.
Just out of curiosity, I did a search on newer CPUs, there's an i3 that's even more capable and eats even less power.
It's not a priority at all, but this PC should live even longer, if I get my hands on one of those later down the line.
Whatever the case may be, it won't be sitting around getting dust and moth.
 
Thanks a lot for your support, guys.

I also found this one: https://deepcool.com/product/powersupply/2014-02/10_689.shtml
Their DA series are mentioned in Tier C...
The price difference isn't that steep, and maybe it will hold a possible CPU upgrade. (if I ever find a second hand CPU that fits)

I mean yea it has less to fail, but fans just don't fail often now. Id keep the current cooler for now.
 
Yea speed will be more than plenty. A single hdd can stream 4+ 4k steams easily. Your gonna be network limited first normallty
 
WIth current hdd pricing id get the exos drives, there normally cheaper than the ironwolfs and better.
 
Or get the cheaper external drives, probaby a bit worse, but the price savings makes up for failure rate easily