Make sure all power connections on the mb are made (there are more than just the 24 pin).

Ohh mate that was it. I hadn't connected the PSU CPU cable. Now it works: https://streamable.com/9bwg1k

Thank you so much!!

Make sure only the correct mb standoffs are installed and all of the correct standoffs are installed and used. Looks like there is an unused mount in one of your pictures.

Well noticed. I totally forgot to move the 2 remaining MB standoffs. Thank you so much!!

Locate you POST diagnosis LEDs (usually top right of the motherboard). Are any of them on? If so, there’s your problem.

I found multiple supposedly LEDs both at the top right and bottom right, but none of them are on.

Would help to have more info like config

• CPU: Intel Core i9-12900K
• iGPU: Intel UHD Graphics 770
• Motherboard: GIGABYTE B760M AORUS ELITE
• Power supply unit: Corsair CV 650
• Primary memory RAM: CORSAIR Vengeance 32GB DDR5 (2 x 16GB)
• Secondary memory SSD: Western Digital WD BLACK SN770 M.2 2280 1TB
• CPU Cooler: Cooler Master Hyper 212
• Case: Corsair 220T RGB
• Monitor: LG 24MK430H 24"
• Keyboard: Logitech K120 USB

and where you plugged everything in.

What exactly do you mean?

you plugged in your ram wrong. If you only have 2 sticks, they should never be touching, to take advantage of dual-channel. Refer to your motherboards manual

thanks, I just set it according to mobo manual pg 15 for 2 modules

Are the mouse and keyboard plugged into ports on the motherboard I/O panel?

Yes. See

Does the motherboard support the processor/RAM you’re using?

Gigabyte B760M AORUS ELITE (rev. 1.x) says it supports "Dual Channel DDR5：4*SMD DIMMs with XMP 3.0 Memory Module Support". My memory is CORSAIR Vengeance 32GB DDR5 (2 x 16GB).

Is the RAM seated correctly?

Yes. See https://streamable.com/2wmyvd

Does your motherboard support onboard video? Does your CPU have onboard graphics? If you’re using a separate GPU, is your monitor plugged into the GPU, or the motherboard?

CPU is an i9-12900K. It has Intel UHD Graphics 770 according to https://ark.intel.com/content/www/us/en/ark/products/134599/intel-core-i912900k-processor-30m-cache-up-to-5-20-ghz.html

Are you getting any error lights?

According to page 20 in mobo manual

These should be the LEDs indicating CPU, RAM, etc, but they aren't on it seems. So I suppose from what the manual says they're working?

What components are you using (motherboard, processor, RAM, video card, etc)?

• CPU: Intel Core i9-12900K
• iGPU: Intel UHD Graphics 770
• Motherboard: GIGABYTE B760M AORUS ELITE
• Power supply unit: Corsair CV 650
• Primary memory RAM: CORSAIR Vengeance 32GB DDR5 (2 x 16GB)
• Secondary memory SSD: Western Digital WD BLACK SN770 M.2 2280 1TB
• CPU Cooler: Cooler Master Hyper 212
• Case: Corsair 220T RGB
• Monitor: LG 24MK430H 24"
• Keybaord: Logitech K120 USB

CPU is an i9-12900K. It has Intel® UHD Graphics 770 according to https://ark.intel.com/content/www/us/en/ark/products/134599/intel-core-i912900k-processor-30m-cache-up-to-5-20-ghz.html

Motherboard is Gigabyte B760M