CptBligh

More RAM will only help if you are exceeding the physical memory usage, symptoms are usually prolonged stutters where the system begins paging memory to your hard disk. You can use something like HWINFO64 to monitor this and many other things. It has no affect on graphic quality nor will it give you faster frame rate. Your system is pretty old for a good VR experience. Throwing in a 5800X3D, 32GB RAM (64GB for large online servers) and a new GPU would go a long way, but you're mostly to the point of needing a whole new system. I can't help with your other questions related to the Quest.

@TED is the only active poster I recall with a 7900 and he likes it. Several of us have 6900s that have been fine, but I think it's general agreement with most that team green is better at VR. I'm looking at grabbing a 4080/4090 for use with Varjo Aero since my Reverb died and Varjo doesn't support AMD.

7900, 4080 or wait for 4080 Super end of January. 6900XT with Reverb here

My 6900XT has been fine in DCS and IL2 though it could always be better of course. My biggest issue seeing that you're also a Reverb issue is that the Varjo headsets only work with team green if that is a possible upgrade consideration in the future. I would've already pulled the trigger on the Aero myself but I'm kinda in the same boat as you right now regarding GPU.

It's hard for me to recommend the current gen GPUs when they have now been out for a year with no real decrease in price. Maybe the 4xxx Super releases in January will provide some pressure. I'm biased, but if you can still find a 6900/6950xt or RTX 3080 in the $500 range it's a pretty decent value to get by until hopefully the RTX 5xxx. Dropping $2k on a 4090 at this date just doesn't make sense to me.

7800X3D would be the go to CPU especially for MSFS in my opinion.

7950X3D is 8x3d/16c/32t but as Sharpe said the actual image quality should have very little to do with the CPU. I would turn all of the DLSS/DLAA stuff off first and go from there.

While Intel has supported subsequent generations of CPUs on some chipsets, they were hardly worth bothering with to upgrade assuming like for like tiers. My X99 Haswell-E system never went to Broadwell-E, and now I'll never upgrade on Z690 from my 12700k as 13th and 14th gen hasn't brought anything to the table just like those prior gens you mentioned. Someone who went from a R7 1700 to a R7 5800 had a hell of a upgrade, though admittedly it was probably a tiny minority that lucked into that situation. And of course no guarantees that AM5 will have the meaningful generational improvement that AM4 saw either.

I would also be looking at AM5 at this point instead of buying into a dead end platform with Intel. You may not ever need to upgrade the CPU again but at least the option would be there.

Have you tried enabling safe mode in Open XRTK application?

I assumed that's what Bignewy meant. I run my G2 this way and it has never bothered me and I prefer it instead of 45FPS motion repro

Nice score, but the CPU usage going down is mostly just a function of having more cores.

I would also say you're probably due for a total system upgrade without one component hamstringing the others too much. Should be able to find a 7800XT/6900XT/6950XT in that $4-500 range which I think would give the most improvement for the time being. I wouldn't spend the time and money swapping out for a 9900k personally - that $200 will buy a new 12th gen CPU now, and probably a 13th gen when the 14s come out end of this year. Get a DDR4 Z690/Z790 motherboard so you can reuse your current RAM.

@TED has one I believe. My 6900XT has worked well. I bought it January 2022 when I couldn't find any geforce cards in stock that weren't scalper prices.

Try updating your motherboard BIOS to the latest version if haven't already. I would exchange it if it won't hit it's rated speed since you paid for it. You likely won't see any meaningful difference regardless though.