I’ve got something about the ram.
I’m using a 8700k.
DDR4 16 GB 2133MHz
I know change from 16 gb to 32 to improve performance is futile.
I’ve seen video benches with difference between 2133Mhz to 3600MHz running on 8700k.
it’s different on each resolution… And of course the optimization of the game.
But this is the question: Does the effect change when switching to 2133 to 3200 OR 3600 MHZ on the pimax 5k+ ?
Should i do it?
tl;dr Probably won’t make a substantial difference for regular use because the main bottleneck is the GPU.
I have 32GB of 3200 MHz RAM CAS 14. I previously ran that non a non-K variant of 8700 CPU. My GPU is a water cooled 1080 Ti. The fastest the 8700 CPU would let me run my RAM was 2666MHz (because 3200 is considered an “overclock” by Intel). So I upgraded to a 9700k and now my RAM runs at the proper XMP profile (3200 MHz, CAS 14). I haven’t noticed any improvements. I ran some benchmarks before and after and the scores went up, but only like +1-2 fps. I think the main bottleneck is GPU for any resolution above 1080p (including the 5K+)
That is what almost all benchmarks show.
i have to because i have 2133 mhz that’s way to low.
I’m going for 3200mhz.
But i’m still stuck… witch CL i should get, 14,15 or 16?
G.SKILL OR corsair.
I would go for 3200MHz CL14, but it depends if You’re willing to pay the extra cost for it for something You probably won’t notice in most games (I would… Go for it that is).
EDIT: You can most likely verify compatible RAM on Your motherboards manufacturers website (or we can help You if You find the make+model). - Too late 
Make sure your motherboard is compatible with the memory you are getting and what CL. Also do not put ECC memory in unless your board allows it (I suspect it does not)
Already checked, it’s compatible with Asrock z370 Extreme4, not the ECC of course…
But the CL15 is like 250 euros more expensive in my country then the CL 16.
So yeah not worth it…
the price is still going down on the CL16. im waiting when price hits the ground.
waiting for the 5k+ anyway 
I would probably just go with 16GB lower CL RAM rather than 32GB higher CL. 2x8GB sticks leaving 2 slots free and buy two more stick later if the “need” arises… 
I’ve got 24GB RAM in my rig but I’ve never noticed a usage of more than ~12-14GB while gaming.
If you wanna know.
Going for:
Corsair Vengeance LPX Black 16GB DDR4-3200 CL16
I got 32gb 3600mhz CL19. I’m pairing it with a I7 9700K, and RTX 2080 TI for the 5k+. I’m not a big teck guy still learning. Lol! I didn’t know anything about CL until reading some comments between Sweviver and another backer on the forum. After I already purchased the ram. I thought I got a good deal on under $240 on eBay. My question is will this ram lack performance because of the CL?
For the i7 9700k?
You wont get any lack performance because of the CL.
You dont have to worry