Sorry to hear that. Frustrating. Probably is worth contacting Asus support and discussing a return. Seems to me that a faulty motherboard is certainly a possibility
😞It could also be a problematic CPU, but on balance of probabilities, probably more likely to be the motherboard I think.
Z690 Hero, BIOS 3401, MEI 2345.5.3.0, ME Firmware 16.1.30.2361, 7000X Case, RM1000x PSU, i9 12900K, ASUS TUF OC 3090TI, 2 x 16GB Corsair RAM @ 5200MHz, Windows 11 Pro 23H2, Corsair H150i Elite AIO, 4x Corsair RGB fans, 3x M.2 NVME drives, 2x SATA SSDs, 2x SATA HDs.