HP Laptop not booting

[Atds19990]

Got a HP Probook 450 g5 that will not boot. I press the on button and it will turn the LED on for a second then turn off no beep code or led code to show where the issue is it just turns on then off again. If I take the RAM out it will do a beep code for RAM not being seated correctly. But that is all I can get. I have stripped it to every individual component used compressed air on mobo to make sure jo dirt etc creating and issue and then re built still doing the same thing. Any suggestions? I have been through the obvious like do a hard reboot. I have changed the RAM with another stick same size memory and mHz. I have tried a different AC adapter. And have tried booting without RAM or the nvme installed to see if that was the issue but it still won’t boot.

I assume the issue is MOBO the internal battery or cpu but is there anything else I can test or do to try get it to boot before having to give in and get it recycled?

 

Thanks could really do with assistance on this one!!

[gmonks]

Have you tried removing the power and battery, holding the power button down for 10 seconds then trying again?

 

Has worked for me many times over the years.

[Jawloms]

If this is one where you can't remove the battery (like the G4 450 we have) then unplug it and press and hold the power button and mute button for 20 seconds, then plug it back in and try powering it up again.

[SteveB_NI]

Exact same issue here - this fixes it for me.

 

Noticed it’s because CMOS has issues with laptops not being used much at present with lockdown etc.

[DaveTheTech]

Do the cap locks and num lock leds light up?

[Oaktech]

Boss has one... This happens every couple of months. Usually the 20 second press fixes it. Once I've had to dismantle it and physically remove the battery and press the button for 10 before it came back to life.