All in one no display (nothing at all) during start up

[T3RR1B13_5N1P3R]

for context: i toke apart the all in one and the cpu fan to clean the dust since it’s been a good 8 months, i toke out the ram sticks out too, everything went back to where it is suppose to be yet when i booted it the screen doesn’t show anything. No logo, nothing. The computer itself IS running, the sound and the fan are both working. No there is no beeping, it’s just an empty screen. 

as soon as it didn’t start showing anything i toke it apart again to see if i messed up something, i switched the position of the ram sticks, checked if everything was in place, and i found nothing that was out of their positions.

Any help? The computer was bought in China and i remember something like this happening before when i upgraded my HDD and ram, while swapping the cd rom with a SSD, but force shut down fixed it before...it isn’t working now.

The model i believe is just HP TouchSmart 300, it looks like the 300-1020, but some of the specs aren’t the same, don’t know if any of this is helpful.

[WAWood]

@T3RR1B13_5N1P3R 

Wish I had good news for you, but I don't.

While disassembling a PC does not, in and of itself, void the HP warranty, if there is any damage done to it while it is open, that generally DOES.  And that would result in either HP charging you dearly to fix it, or possibly even refusing to fix it.

But, to get an OFFICIAL response on this, you would need to contact an HP Repair or Service Center.

If you live in the U.S., here is a link to the HP Service Repair Centers:
https://www.service-center-locator.com/hp-hewlett-packard/hp-hewlett-packard-service-center.htm

If you live outside the U.S., here is a link to HP Service Centers, by Country/Region: https://support.hp.com/in-en/service-center

Good Luck