[SOLVED] How to Identify if the motherboard is bad/broken/dead?

[galaxymark1994]

So what really happen is everything is working fine and i decided to clean my pc parts since it's been more than 6 months since the last time i clean my pc and the dust are really visible already(visible dust but not severe). I used paintbrush and blower then put everything back and the PC won't stay on anymore. I'm stuck on boot loop.this happens before and i just tried the basic troubleshooting and it works but this time it's not letting me get back in business anymore.

What I've tried so far.(without the Videocard)

1. removing all Fans(except CPU fan) and trying to boot again
2. removing the RAM
3. removing all USB connectors
4. removing sata connections
5. removing the CMOS battery for few seconds and putting it back.
6. testing the PSU (paperclip test) - the PSU works and that's while the Molex type Fans are connected.
   

The last thing i tried is booting the motherboard without the 4+4 Pin and it's still the same. I also checked if the motherboard pins are bent and it looks like no damage at all.
I'm using GIGABYTE B250M Gaming 5 .

I hope you have any other option or ideas to help me revive my PC again. thank you.

 

[Eximo]

Any beeps? Post codes (doesn't appear to have a display) Lights on the board?

Have you tested the power supply voltages? Just because it can spin a fan doesn't mean it is working correctly. Have to check if the 12V, 5V, and 3.3 volt are good (at least open circuit, still not a guarantee) So if you have access to a multimeter, that would be good. (if not, you can get one for about $15-20, very useful to have around)

First thing, take the board out of the computer and test it in isolation. (breadboard, as if you were first testing) Not too difficult to have gotten something shorted under the right circumstances. Glitter is pretty bad (My mother ran a cosmetics store, if you can imagine the dust inside the sales computer...)

Being able to manhandle the board might make it obvious what is wrong. Perhaps you knocked a component off?

Static damage is always a possibility when using a brush. They do sell anti-static brushes, but they are no guarantee since what you are brushing isn't always anti-static itself.

Beyond that, you need known good working components for a comprehensive test. Sometimes your local computer shop is your best bet.

 

[galaxymark1994]

Any beeps? Post codes (doesn't appear to have a display) Lights on the board?

my motherboard doesn't have built in(or external motherboard speaker) and I missed the part of connecting regular speaker on it but will try it that will work with diagnostic beeps.

Have you tested the power supply voltages?

well this one doesn't comes in my mind and thank you, I can borrow one from someone who has and will also try it.

Perhaps you knocked a component off?

I don't really think so since i usually handle every component with extra care.

Static damage is always a possibility when using a brush

regarding this, i used the regular paintbrush and cover the metal part with electrical tape. this is what I'm afraid of since i don't use the anti-static strap but I often touch the metal case part and the anti-static bag(if the anti static bag really works) before touching the components again. and I worked as an electrician before been electrified multiple times already I don't know if that will make me more prone to ESD.

I'll try those couple things you told me and will give an update here later, thank you