Replace MSI B450M Mortar Max but keep existing components

[dunxd]

My 12 year old son's gaming rig has been playing up for a while. Some days it won't power on, other days it does. When it won't power on, the EZDiag light on the motherboard is lit up on CPU. When it does power on my son is more than happy with the performance for the games he plays.

The motherboard is an MSI B450M Mortar Max. I bought a new CPU (Ryzen 5 4500) to replace the Ryzen 5 3400G, but when I switched them over that also isn't working. I managed to get it up and running yesterday with the 3400G after taking all the components out and putting them back one by one, but this morning no luck. I updated the BIOS on the board a couple of months ago while it was powering on, to try and resolve the intermittent issue so I don't think it is a compatibility issue.

Am I right in thinking the problem is with the motherboard?

If so, what motherboards can I replace the B450M Mortar Max with that will support the Ryzen 5 4500, DDR4 RAM and fit in the mini ATX case? I'm ok with an upgrade of the motherboard but not ready to replace the whole thing yet.

 

[dunxd]

Just to add the case is an Aero One Mini

 

[dunxd]

It could be something silly like the switch on the case. It could also be the power supply.

Swapped out the power supply under warranty six months ago as it had failed completely.

How would I check the switch on the case? It definitely switches the PC on and off.

 

[dunxd]

What might or might not work (depends on the BIOS): A320/520, B350/B450, X570.

Sorry - I don't understand what you mean here. If I go for a B550 then am I covered?

Looks like the ones that fit in the case are:

* Gigabyte B550M DS3H (AMD AM4) B550 Micro-ATX Motherboard
* MSI B550M PRO-VDH WiFi (AMD AM4) B550 Micro-ATX Motherboard
* Asus TUF Gaming B550M-Plus WIFI II (AMD AM4) B550 Micro-ATX Motherboard

With only the Gigabyte available for purchase today at Overclockers, but all available ***elsewhere*** including the non WiFi variants. *** no competitor links ***

 

[dunxd]

Thanks for clarifying. *** No competitor links ***

I'm ok with flashing new BIOS, but after having one board (possibly) failing I am a bit reluctant to go used.

 

[dunxd]

Can't really check it
Well not easily
If you have a multimeter
Or just use a led and couple wires and a battery etc
Then you could

Other way would be if the motherboard
Has built in on/off button
Not looked up your board but usually
It's higher end board has them

Could just disconnect the on/off wires from
The motherboard
And try turning it on a few times
By jumping the 2 pins with a screwdriver or similar
If that consistently works
And on/off switch doesn't yes might be switch

 

[dunxd]

The on/off is working ok. The fans all start and there is power to the motherboard but the CPU light on EZDiag comes on so no boot.

 

[dunxd]

I also found the GIGABYTE B550M AORUS ELITE which looks viable. Also the Asus Prime B550M-K. Any thoughts?