New PC, won't POST

[knockoutZ]

Hi all.

 

I just built a new PC and it won't POST. Have gone though the POST sticky and troubleshooted everything, still no go.

 

Intel 10400F

ASUS TUF B460-PLUS

G-Skill Aegis 16GB 3200 DDR4

 

System is currently open workbench, with only MB+CPU+RAM+GPU connected. 

 

Mobo has 4 debug leds: 

 

CPU

RAM

GPU

Boot [yellow and green]

 

It goes like this: CPU then RAM leds flash, one after the other, then it GPU led turns on. This one stays on. After about 3 seconds, Boot led turns on and goes to green. Both GPU and Boot leds stay on. Going by ASUS support page, this means there are some problems with the GPU. Fans turn on, display stays off.

 

What I've tried (using parts from working PCs):

- 2 different GPUs  

- both PCIe 16x slots of the motherboard

- 2 different PSUs

- rebuild, checking the Mobo socket pins and CPU contacts for any abnormality

 

All this made no difference

 

Is there a way to check MB BIOS version? On ASUS support page it says my CPU is supported starting BIOS ver 0401 which is one of the initial BIOSes.

 

What to do? I'm out of ideas.