Eajimoba

Looking into early reasons why MSI boards were the most harshly affected now that I've really ascertained what's going on, they seem to have the most aggressive voltages for the SOC and IF in XMP mode over other boards.  Until I passed 3866, my I'd get WHEA errors if my SOC voltage was 1.1, which is MSI's XMP auto setting.
 
Once I needed the voltage for IF stability, it was the opposite.
 
From preliminary findings I'd start with 1 volt SOC, 0.900 VDDG voltages and bump as needed when going up the ladder.  It seems what causes errors at one point, might not at another.  Entering these manually should also work for XMP profiles on Zen 3, not just manual OCing.  Should be a fix in lieu of a BIOS update

It's all coming down to SOC voltage.  I have tons of leeway on VDDG voltage, Im back down to stock 0.900 voltage, but I have to be within .02 volts of a certain point in SOC voltage once I get above 3666. 
Too high: instability.  To low: instability.  While this was somewhat the case with Zen 2, the sensitivity of IF to SOC voltage is on a whole other level with Zen 3.
I got it to 1933 before I hit a wall @ 1967 that both going lower and higher on SOC voltage results in more instability.  But I was still able to post unlike the wall I hit with Zen 2 at 1900.
 
Also, for the first time, I'm seeing scaling in IF with voltage that is directly proportional.  Didn't see any type of linear scaling with my 3600 (Zen 2) and 1700 (Zen).  The returns were disproportional to any voltage applied.  The only time applying more voltage was useful for IF was if you were on the threshold of stability.

Alright, had time to do more testing, moving to dialing in ram.  This is my procedure for dialing in your Zen 3 IF.  Posted to reddit, getting feedback of success on other MBs as well. 
BETA GUIDE TO DIALING IN ZEN 3 INFINITY FABRIC
1.  Set SOC voltage to 1.0, both VDDG voltages to 0.900, and ram to 2133 16-20-20-20-40 to eliminate any chance of a fluke RAM error
2.  Set FCLK to 1600.
3.  Test with AIDA64, OCCT 30 minutes each.  Confirm stability.
4.  If unstable, increasing and decreasing SOC voltages in .025 steps.  Max SOC voltage is 1.2
5.  If you hit an SOC wall where you reach 1.2 volts or changing voltage either way increases the WHEA error rate, trying increasing VDDG voltages in 0.025 increments  Remember that VDDG voltages can only be .05 volts below SOC voltage at the most (they can go as low as stable) as infinity fabric voltage is directly derived from the SOC voltage.
6.  Dial up FCLK one notch at a time.  Repeat step 3.
7.  If instability, repeat steps 4-5
8.  For final stability test at desired FCLK, run both AIDA64 and OCCT for an hour each.
9.  Bring your RAM frequency up to match and begin dialing in timings as normal.
 

for the quantum version here is the layout 

Radiator/pump combo? Do you mean pump/res? Regarding the 360 rad, no that's just the measurements for the fans. a 360 is made for 3x120mm fans, radiators will have the "head" and other parts that extend past the holes for the screws which means that various rads won't work in more cramped areas.
 
For the vertical GPU mount, you're right that you can't do a radiator underneath it too. Even if you had a slim rad+fans I'm not sure you could fit them under a vertical mount.
 
For the EVGA question, you might be able to do that, I'm not sure and would do some more investigation. I'm not sure that it will be intelligent enough to run a fan curve without software, it could but this isn't something I can say is definitely the case
 
If you can make back most of your money on the 3090 and went AMD then great, we'll see how things go, I wouldn't mind going back to a full AMD system. The least issues I've had were when I had full AMD..
 
I didn't realise you already had the monitor. Personally I would go for the additional size but that's me, I like a lot of screen real estate!
 
I've seen people doing distro plates like you would need in 1 of 2 ways, but honestly this seems to have always been an afterthought where they couldn't get a GPU block etc. Depending on the distro you can put caps onto the ports you won't use so that they stay clear of dust.
 
If you can/want to make more use of the plate, you can just use fittings to transfer liquid from 1 section to the next. So you would connect the port that would push liquid to the CPU and the one that would come from the CPU, this would transfer the liquid from one channel to the other to continue the loop.
 
Here's a video demonstrating it: 
If you go to 1:44, you'll see that he's doing a tube from 1 channel in the distro to another channel in the distro, this is bypassing the component it was intended for. In your case you would just do it for the CPU instead.

That’s just way to much money imo. Money that would be better spent almost anywhere else. More SSD space, better GPU, in your pocket, literally anything is better than 360 bucks on RAM.... 3600 CL16 is basically the best you can get. Faster or lower latency is for benchmark chasing. If you really, really want to spend that money, spend it on a 5900x, don’t spend it on RAM. Faster CPU will make a much larger difference than faster ram.

The difference is not worth $120, so you probably better with the 3600, it has tighter timings.
Make sure it's a 2x kit not 4x.

Noted, thanks!
 
Literally updated my shopping cart just now hehe

The difference between the two are only interesting for benchmark scores. In practice, I don't think you'll notice any difference.

The 3600 kit would make more sense. 
 
Ryzen 3xxx processors work best with up to around 3733-ish Mhz memory, due to Infinity Fabric, so everyone recommended 3600 MHz memory sticks. 
 
With the 5xxx series, they may raise the Infinity Fabric abilities up to the point where 4000 Mhz may be the optimal memory, but I suspect the differences in performance between 3600 and 4000 Mhz will be super small, especially as the timings are looser at CL17 for the 4000 mhz memory. 
 
It's just not worth the extra 120$ ... you'll get more overall performance out of your system by placing that 120$ into a better motherboard, or a better video card. 
Also, you could probably get 32 GB 3600 Mhz for less than $400 and get about the same performance, but less overclocking potential and less bling (rgb, shiny heatsinks etc)