Question New build turns on but no POST, LED on mobo changing?

mreitz.dmu

Prominent
Nov 3, 2018
6
0
510
Solved- solution below

New build with these specs, all new parts:

MSI B550M PRO-VDH WIFI Micro ATX AM4 Motherboard
AMD Ryzen 7 3700X 3.6 GHz 8-Core Processor
G.Skill Ripjaws V Series 32 GB (2 x 16 GB) DDR4-3200 CL16 Memory
HP EX920 1 TB M.2-2280 NVME Solid State Drive
NVIDIA GeForce RTX 3070 8 GB Founders Edition Video Card
Corsair SF 600 W 80+ Gold Certified Fully Modular SFX Power Supply

PCPartpicker does not mention any incompatibilities in the above parts.

The computer powers up, all the fans turn on including the CPU and GPU, and the power button LED turns on, but no bios comes up on screen. The motherboard LED light up white, and alternates between CPU, VGA, BOOT, and DRAM usually one at a time or none at all. The mobo LED may stay on CPU for a 20 seconds to a minute and then will go off, and the VGA LED will go on, then it may turn off for 20 seconds and another LED will come on. There doesn't seem to be a pattern to it either.

I tried disconnecting the GPU and using just a single stick of ram in different slots, with the same results. Plugging the HDMI cable into the GPU or motherboard doesn't make a difference.


Thank you in advance.
 
Last edited:

mreitz.dmu

Prominent
Nov 3, 2018
6
0
510
Motherboard may need BIOS update to support Ryzen 3000 series CPU -- was anything printed on the front of the motherboard box about it being "Ryzen 3000 Desktop Ready" ?

On the front of the motherboard box, it says "3rd gen AMD Ryzen Desktop processor compatible", and "3rd gen AMD Ryzen desktop ready", so I believe so.
 
Ryzen 7 3700X is 3rd generation so it shouldn't need a BIOS update according to the mobo box, but I could be mistaken. Don't know what else to suggest.

Incidentally, you said you tried plugging monitor in to the motherboard --- that won't work anyway because your CPU does not have an integrated graphics processor.
 

mreitz.dmu

Prominent
Nov 3, 2018
6
0
510
Took it to a repair center.
Turns out there were two problems-
  1. The CPU needed reseating and
  2. The PCI slot for the graphics card wasn't working, needed a new motherboard