Question MOBO XMP Issue

[Hyziu]

Hello Everyone!

I'm having issues with my new build, PC won't turn on when I use optimised RAM slots (A2,B2) but will boot up when RAM is in A1,A2 however speed is locked at 2666MHz.

RAM Corsair Vengeance LPX Black 32GB 3600MHz 2x16GB DDR4
MOBO MSI PRO B660M-A WIFI DDR4 Intel Motherboard

BIOS is updated to the latest version, MOBO Led lights flash red for CPU and RAM when using the optimised slots. Any help is greatly appreciated

 

[rgd1101]

full system spec?

 

[Hyziu]

full system spec?

Good Morning!

CPU Intel Core i7 12700 Alder Lake-S CPU
CPU Cooler Be Quiet! Dark Rock 4 CPU Air Tower Cooler
RAM Corsair Vengeance LPX Black 32GB 3600MHz 2x16GB DDR4
MOBO MSI PRO B660M-A WIFI DDR4 Intel Motherboard
Storage Crucial P2 1TB M.2-2280 PCIe 3.0 x4 NVMe SSD
Video Card RTX 3070Ti
Case Lian Li Lancool II Mesh RGB Mid Tower Gaming Case
Power Supply Corsair RM Series RM850 850W Modular 80+ Gold PSU
OS Windows 10 Pro

 

[egda23]

Win 10 fresh install, or transfered SSD from old PC?
Do a clear CMOS, and put RAM back in A2 B2, reboot.
After that, switch off. Boot, go in Bios and enable XMP

 

[Hyziu]

Win 10 fresh install, or transfered SSD from old PC?
Do a clear CMOS, and put RAM back in A2 B2, reboot.
After that, switch off. Boot, go in Bios and enable XMP

Fresh install.
I tried to clear CMOS yesterday but will have one more go tonight. Thank you!

EDIT UPDATE

Clearing CMOS did nothing once again, single stick of RAM works in A1/A2 however when inserting second stick of RAM in B1/B2 the CPU flashes red and DRAM flashes amber.