I have your manual up on my screen.
Is your graphics card PCIe 3.0 or 4.0?
Is your primary M.2 SSD PCIe 3.0 or 4.0?
YES! If you're now using an 11900K, you have full use of PCIe 4.0 speed/connectivity in M.2_1 - the M.2 slot directly adjacent to your CPU socket.
Your M.2_1 slot is PCIe 4.0
Your M.2_2 slot is PCIe 4.0...Both feed from CPU lanes, not chipset lanes.
Your other two M.2 slots feed from the Z590 chipset are PCIe 3.0 thus slower.
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Your primary boot drive NVMe M.2 PCIe 4.0 SSD should install in M.2_1, closest to the CPU will give you the greatest speed.
Your primary storage drive NVMe M.2 PCIe 4.0 SSD should install in M.2_2
If both your M.2s are PCIe 3.0, grab at least one WD_Black SN850 PCIe 4.0 M.2 drive for $79 500GB, you will LOVE the speed and responsiveness.
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Your graphics card is either PCIe 3.0 or PCIe 4.0, installing into a motherboard with PCI 4.0 slot WILL NOT change that designation.
Same for your M.2 SSD drives. They are PCIe 3.0 or 4.0.
Although:
If your graphics card is PCIe 3.0 and uses 16x lanes physically and only 8x lanes electrically, and you mount it in a PCIe 4.0 slot it will use half it's normal lanes OR only 4x lanes.
If your graphics card is PCIe 4.0 and uses only 8x lanes electrically and you mount it in a PCIe 4.0 slot it will use 8x lanes.
Z790 Epiphenomenal Raptor Bench
ROG Z790 Apex / Intel 13900KS SP111 P121 E93 MC83
Gskill 8000 kit - TM5 stable at 8200MT/s 38 48 48 121 VDD and VDDQ 1.5v
WD_Black SN850X 1TB 7300MB/s Reads 6300MB/s Writes
LG 32in 4K IPS 32UP83A-W