tomorrow I will get the pieces for my new PC:
- RTX 3090 Founders Edition
- Ryzen 5900X
- B550 MSI Pro Carbon WiFi Mainboard
- 750W PSU
Currently I have 4x8GB DDR4 RAM (Corsair Vengeance) - 15-15-15-36
Do you recommend me to also upgrade the RAM to 3600mhz or 4000mhz to gain even more Fps?
First thing I see is that your current ram is not not symmetrical. This will be preventing your system from fully utilizing the advantage of dual-channel.
Two routes to go here throttle your 36 to 15, not my first choice. You likely won’t see any improvement as the pairs aren’t matched otherwise.
Get three more 8GB 3600, better choice. Just make sure the new sticks are an exact match for the existing.
I would expect to see more performance from having two matched pairs running dual channel than any particular increase due to clock. Obviously 36 is faster than 15 but it won’t be as significant as matching the sticks to begin with.
The performance gains are going to be negligible. I would expect smoother performance rather than faster.