It’s hard to recommend either the RTX 4080 or RX 7900 XT(X) at their current price/performance.
If you have a 4K 120+Hz panel and you need the absolute best-of-the-best with maxed out RT settings, etc. and money is no object, just get an RTX 4090.
Otherwise, if you need 24GB VRAM and/or CUDA for occasional productivity work, look for an RTX 3090 or 3090 Ti around $900.
Otherwise, if you strongly prioritize RT/DLSS, look for an RTX 3080, 3080 12GB, or 3080 Ti around $700–800. To be absolutely clear, if you’re just gaming it doesn’t make sense to step up to a 3090 from this price point. Also please note that this is the tier most likely to see significant price cuts or at least price volatility when the AD104-based RTX 4070 and 4070 Ti launch in January and/or if NVIDIA lowers prices on AD103 silicon.
Otherwise, the best high-end value right now is an RX 6800 XT around $530–560, or possibly an RX 6900 XT around $600. Don’t pay any more than that for a binned 6900 XTX(H) or 6950 XT; a 6900 XT at $600 is already past the point of diminishing returns.
I have more notes for e.g. high-refresh 1440p, entry-level CUDA, mid-range value, etc., but you appear to be shopping on a champagne budget so I’ll leave it there.
DDR5 is a non-starter for me today due to lack of 64GB DIMMs, lack of single-rank 32GB DIMMs, poor 2DPC scaling on both LGA1700 and AM5, etc.
AM5 is a non-starter for me today due to poor IOMMU groupings and limited PCH bandwidth. I am waiting for an AM5 platform with a PCIe Gen4 x8 or Gen5 x4 chipset link before considering an upgrade.
I am also flummoxed by this generation of both Intel and AMD consumer platforms due to the lack of PCIe Express Graphics (PEG) bifurcation. It used to be that every ~$200 board could run two expansion cards connected to the CPU at x8. Now it’s a $500+ board feature. I’m hopeful this will normalize again once PCIe Gen5 matures and PCB manufacturing technology has a chance to catch up.
If you aren’t bound by such requirements, more power to you. Please note that the sweet spot for AM5 is DDR5-6000 (CL38 or better) and you should look for a kit with EXPO (AMD’s XMP-like standard for DDR5 on AM5).
One last note: the i9-13900K(F) is kind of bonkers. It gives the impression that it only exists so Intel can say, “Yes, we also have a 32-thread part on consumer desktop.” If you have a good use-case for all those E-cores, go nuts. If you don’t, I think the 13700K(F) is a much better value. I actually really like the 13600K(F) and 12600K(F) because you can overclock the heck out of the six P-cores with a modest thermal solution and you still get eight or four E-cores respectively.
Still trying to keep it within the realm of reason, of course, but yes… This will last you for the next 5 years, if not 10 years, without a hitch. And the best part is that you will be able to drop in upgrade to the 10950X, due to be released by AMD in 3 years or so!