Question ASRock B650M-HDV/M.2 LEDs cycling but won't POST

[wozl_]

CPU: AMD Ryzen 7 7800X3D 4.2 GHz 8-Core Processor
CPU Cooler: Thermalright Phantom Spirit EVO 69 CFM CPU Cooler
Motherboard: ASRock B650M-HDV/M.2 Micro ATX AM5 Motherboard
Memory: Patriot Viper Venom 32 GB (2 x 16 GB) DDR5-6400 CL32 Memory
Storage: Western Digital Black SN850X 1 TB M.2-2280 PCIe 4.0 X4 NVME Solid State
Video Card: Gigabyte WINDFORCE OC GeForce RTX 4060 8 GB Video Card
Power Supply: ADATA XPG Core Reactor II 850 W 80+ Gold Certified Fully Modular ATX Power Supply

The motherboard LEDs are cycling between DRAM+CPU to Boot+VGA, then all 4 light up and the cycle repeats until I shut it down. Things I've tried include:
- Booting outside of the case on a non-conductive surface
- RMA'd mobo (issue persists with replacement)
- RMA'd CPU (issue persists with replacement)
- Reseated everything multiple times
- Different PSU with new cables
- Different GPU
- RAM in every slot configuration, together and separately
- HDMI instead of DP
- Cleared CMOS
- Flashed BIOS

I have new RAM on the way, but I'm wracking my brain to see if there's anything else I'm missing or messing up. Any thoughts? I feel like I'm losing it.

 

[COLGeek]

How long are you waiting for the system to start up? New systems can take a bit of time to discover/configure all hardware.

 

[wozl_]

How long are you waiting for the system to start up? New systems can take a bit of time to discover/configure all hardware.

I've let it sit for 15+ minutes and no dice.

 

[COLGeek]

Yep. A minute or two at most should be all that is needed.

Have you tried booting with the GPU removed and using the integrated GPU (7000 series have them)?

Have you ever been able to access the BIOS?

Do you have both the 8-pin and 24-pin power connectors firmly attached to the motherboard and PSU?