RAM Slots didnt work after tighten CPU Cooler and PC crashes from time to time

[Luitek]

Hello,
I have built a custom computer myself and have very strange errors and currently do not know what to do.
Brief info about my hardware:
- Case Lian Li O11 Dynamic XL
- Mainboard Asus ROG Maximus Z790
- CPU Headed Intel i9-13900k
- CPU Cooler EK-Quantum Velocity² Direct Die D-RGB - 1700
- RAM DDR5 2x 32GB Dominator Platinum
- GPU MSI GeForce RTX 4090 GAMING X TRIO
- GPU Cooler EK-Quantum Vector² Master RTX 4090
- Power supply Silverstone HELA 1200R Platinum
- Distro Plate EK-Mana G2 PC-O11D EVO DDC D-RGB
- Radiator 2x EK-Quantum Surface P360M - Black Edition
We were still waiting for a screwdriver from EK at the beginning for the 0.6 torque for the CPU block to not screw it too tight, so it ran about half tightened for about 2-3 weeks flawlessly, we didn't overclock anything but just standalone.
After that time the screwdriver came and I tightened it exactly to the specs, now all of a sudden sometimes the A1 and A2 slot didn't work, that's why we thought it was too tight.
Even after loosening it worked only sometimes and sometimes not, so I used for a while only 32GB in slot A2 error-free.
That's why I thought the A1 slot was defective and after using the A2 and B2 slots, the PC sometimes crashed while you were just in Windows or playing something, but it ran before that sometimes for weeks without problems.
I then updated everything possible and still had the same problems.
So it is a very sporadic problem.
After about two weeks only the slot B1 and B2 work and Dual Channel was no longer possible, I had resigned myself to it and was going to send the motherboard to the manufacturer next cleaning, only last week Sunday it was.
I gambled the whole weekend completely normal and suddenly nothing wanted more, the PC has crashed again and again and had said with 64GB RAM there would be no memory installed : QQ code error 55
Should I only have a stick in it and do a CMOS reset, the system booted again, but crashed after a short time in Windows or after starting a game, so I disassembled the system and sent it back to the manufacturer.
Unfortunately, they wrote me today that everything is fine and tested different RAM bars on all slots to different states of the system without problems.
The board has been there twice now and I don't know what to do, do you have any idea what the problem could be and what else I should send in for warranty?
Thank you for any tips and look forward to hearing from you!

[JohnAb]

Sounds like you've been careful, but I'm thinking that perhaps the motherboard traces under the cooler mounting posts could have damaged, especially if the posts have sharp edges etc. Or, perhaps the surface coating has been damaged and the posts (if metal) could be causing a short if there are no protective washers.

Think I would remove the cooler and posts, check very carefully and if there is any sign of damage try adding thin, non conducting washers under the posts. Then put it all back together with fresh paste and just snug down the cooler. Just not too tight, it only needs to make good even contact. Extra force won't really improve cooling. I might be wrong, but worth checking under the posts I think.   

[kampers]

I have see one mobo z790 apex with damaged contact under the posts. He didn't use a washers under the posts. My question is. Who delivery washers ? 

[JohnAb]

Not sure if they usually come with coolers, but they should. Otherwise I'd just find some on eBay or Amazon. 

[Luitek]

Thanks alot but where should i put the washer`?

[Luitek]

I have once the block that holds the Direct Die CPU and at the same time holds the CPU, that is the small block and then I have the larger one that is on the back of the motherboard, there are the 4 inner screws for the front block and on the outer ones the CPU cooler will be screwed later.

I ordered a few washers on amazon, where should I install them now everywhere?
Only on the outer 4 holes on the back or also on the inner 4?
The inner ones are responsible for the CPU contact pressure.

I thank you for the brief info!

[Luitek]

Pictures:

[kampers]

https://youtu.be/258mCuhm650?si=xZIjSKbQXjG4q8Ks

[Luitek]

I already know the video, at that time construction everything watched with it and the manual to it.
As I said, we proceeded very carefully and yet I probably have some contact problems and even if they do not use washer, I want to install some.
My film is intact and looks completely normal, so the video brings me nothing, then I can do everything once again as before to then disassemble the complete system again.

[kampers]

It's don't look at you need washers becouse your's screw from backplate you mount directly to waterblock. So it's only contact between cpu block and backplate. I think it's like that.  If you look to my manual you can se where I should mount washers. But it's different block.

HEATKILLER® IV Montageanleitung / Assembly Instructions https://shop.watercool.de/mediafiles/Manuals/MA_HK_IV.pdf