2 b450 mobos possibly dead on arrival

In order to help you, you need to post ALL of your exact system specs. Along with the motherboard, you need to post the exact ram you used, exact pw supply, exact video card, etc, etc, etc.

Next have you read the guide at the top of the forum for problem builds? If not, do so.

I tend to think it is something you are doing, mismatched parts, etc. The odds of two consecutive DOA boards are VERY high. With all of the systems I have built [over 500] I have had one DOA board.
You are not by chance attempting to use the onboard port on the motherboard are you?

Ryzen 3 1200
8gb of ddr4 @3000mhz
Evga 850 watt psu gq 80+ gold

And no im not using an on board port.
But even if i was, that wouldn't explain the lack of fan spin.
I made sure to check if i put in the essentials (24 pin for mobo and 8pin cpu pwr for the cpu)

Read the guide and follow the procedure outlined. If you follow ALL of the steps, you will find the cause of your problem.
If you are sure the 4/8/12 aux pw connector is plugged in, I would guess you do not have the board mounted correctly. Did you do an out of case build prior to installing the board in the case?

I did it all outside of the case, on the motherboard's box

OK, you are not answering the question. Did you read and follow ALL steps of the guide?
Getting two DOA motherboards in a row is just about impossible. As I said out of over 500 builds, I have had 1 dead motherboard.

And yeah i have read it
I also tried using my gygabyte rx 570 on the mobo and still nothing.tried to put the ram in all slots as well

Using a cx pw supply in anything other than a very basic build ie onboard/onchip video, is just asking for a problem. Even corsair says the cx or vs series is for a basic system.

If you follow ALL steps of the guide, you will find the cause of your problem.

I also tried an evga 850 watt gq on this earlier. Didn't do anything either. Ill read the guide again to see if i missed anything

Aand it worked.
Im stumped. I did a whole bunch of randok stuff and it worked

Nvm i turned it off and went to get a monitor and i get the same problem again.
Is there something I may be doing wrong here?

I hope you are not trying to start it with the heat sink off like in the pictures.

lynx1021 said:

I hope you are not trying to start it with the heat sink off like in the pictures.

Click to expand...

I was thinking the same thing