URGENT HELP NEEDED: ASUS PRIME B450M-A II Motherboard no power at all!

[BlaGoMax]

Hey everyone,

I'm in a bit of a bind and could really use some advice or guidance. I recently purchased an ASUS PRIME B450M-A II motherboard from Computer Universe, and everything seemed to be running smoothly for about a week after I assembled my PC. However, one morning, without any warning signs, the system just refused to power up - no fans, no display, absolutely no signs of life.

I've exhausted nearly every troubleshooting step I could think of. I've swapped out different components —RAM, CPU, GPU— and checked the power supply, but the only component left seems to be the motherboard itself. I even tried the components on a different known-working motherboard, and everything functioned perfectly. It's puzzling and frustrating because the ASUS motherboard seems to be the culprit, but there's no obvious damage or signs of malfunction.

I've reached out to Computer Universe for support, but unfortunately, they're not shipping or servicing outside of Europe anymore, and I'm in Algeria. ASUS suggested returning the motherboard through the seller, but that's not an option for me due to their current limitations. I've approached several local repair shops, but none have been able to diagnose the issue since there are no visible signs of damage. At this point, I'm feeling a bit stuck. I know the motherboard isn't too expensive, but I'd hate to give up without exploring all possible options.

Has anyone encountered a similar problem before? Any suggestions or guidance would be immensely appreciated. If you have any leads on reliable repair shops or alternative solutions, I'd be incredibly grateful.

Thank you all for your attention and support. Your advice could be a game-changer for me right now!

 

[Chrispy_]

Breadboard it.

Take the motherboard out of the case and put it on a cardboard box.
All you need is a motherboard, CPU (and cooler) and 1 stick of RAM. Depend on what CPU you have, you may also need a dedicated graphics card.

If the minimum viable system isn't bootable, you need to RMA stuff. If it boots, add more RAM and SSDs and/or HDDs one boot at a time. If the whole system boots outside the case, check the case for incorrectly-positioned motherboard standoffs, loose screws etc.

Let us know what happens when you breadboard it. Does the CPU fan spin, are there lights, etc?

 

[BlaGoMax]

Breadboard it.

Take the motherboard out of the case and put it on a cardboard box.
All you need is a motherboard, CPU (and cooler) and 1 stick of RAM. Depend on what CPU you have, you may also need a dedicated graphics card.

View attachment 328986

If the minimum viable system isn't bootable, you need to RMA stuff. If it boots, add more RAM and SSDs and/or HDDs one boot at a time. If the whole system boots outside the case, check the case for incorrectly-positioned motherboard standoffs, loose screws etc.

Let us know what happens when you breadboard it. Does the CPU fan spin, are there lights, etc?

thank you sir for your answer
I've already followed all your instructions, and the issue lies solely with the motherboard—it isn't delivering any power at all. I've tested all the other components (CPU, PSU, RAM) on a different motherboard, and they are functioning perfectly. However, the brand-new motherboard is the only component not functioning.

 

[Chrispy_]

I avoid Asus Prime now; From too many bad experiences, they're built far too cheap and lack diagnostic LEDs of any kind which makes troubleshooting far more effort than it needs to be. Asus always skimps on VRM and cooling for their Prime models, too - just in case you didn't need a second reason to avoid them.

When you send it back as faulty, see if you can get a refund rather than an exact replacement and buy a less basic model from Gigabyte or MSI - both of them make far nicer mid-tier boards for the money Asus ask for their super-barebones Prime series.

https://www.msi.com/Motherboard/B550M-PRO-VDH is a good, cheap board with diagnostic LEDs and a better feature set than the Asus Prime range.

 

[ZenZimZaliben]

It seems the ASUS PRIME B450M-A II doesn't have any diagnostic led's. How about the diagnostic speaker, do you have it hooked up?

 

[PLAfiller]

Have you cleared the CMOS? Like I've had a similar case very recently with an Asus TUF board, spanking new. Working fine, then wouldn't start at all. Used a jumper from an old CD-rom drive, removed the battery and after I cleared the CMOS, the PC started right where it stopped the last time. Give it a shot if you haven't. There is a section in the manual where it says how to clear the CMOS.

 

[BlaGoMax]

I avoid Asus Prime now; From too many bad experiences, they're built far too cheap and lack diagnostic LEDs of any kind which makes troubleshooting far more effort than it needs to be. Asus always skimps on VRM and cooling for their Prime models, too - just in case you didn't need a second reason to avoid them.

When you send it back as faulty, see if you can get a refund rather than an exact replacement and buy a less basic model from Gigabyte or MSI - both of them make far nicer mid-tier boards for the money Asus ask for their super-barebones Prime series.

actually they told me they will refound me without sending it back i don't know how but i really appreciate their help , but yet the situation itself so weird

 

[Chrispy_]

actually they told me they will refound me without sending it back i don't know how but i really appreciate their help , but yet the situation itself so weird

Because it's probably not worth the postage cost when it's a bottom-of-the-barrel board that just died after working successfully, which rules out your PC-building competence and puts the blame solely on the hardware. I suspect it's not their first rodeo with Asus Prime boards suffering infant mortality after a few days and they don't want it back because Asus don't want it back.

For the record, Asus make some really good high-end boards for overclockers and money-no-object enthusiast buids but their entry-level and midrange models are usually best avoided - they're down on features and build quality compared to MSI, Gigabyte, and Asrock at any given price point until you start reaching flagship territory.

I edited my post above to link you a decent cheap alternative that's friendlier to work on and slightly higher quality, but I'll link it again here:

B550M PRO-VDH

Best AMD AM4 B550 MATX motherboard, lightning PCIe 4.0, lightning M.2, USB 3.2 Gen 1, M.2 heatsink, powerful overclocking, MSI PRO

www.msi.com