My hp COMPAQ is booting but not displaying

[ServiceShopKS]

Hello!

I need quick help.I have a COMPAQ laptop and it wont boot is just showing a blank screen (I can clearly see the screen turning on after a few seconds that the laptop is powered on) after i turn it on.

After browsing the internet for a couple of days here are the things i've tried:

1.Reseating everything.

2.Changing its RAM memory and changing its CPU.

3.Tried getting into the bios recovery system by pressing WIN+B(I've tried WIN+V too)

4.Tried to connect it to an external monitor.

5.Tried to talking to the hp service bot.

6.Opened it,cleaned it,looked closely at every part to see if anything is damaged.

[EDIT]7.I've tried removing it's battery and holding the power button for 15 seconds.

Please tell me something else that i can try because its been like this for a while.

Also when i press the brightness up and down keys i can barely see the brightness barely going up and down.

If u could help me i'd appreciate it!!!

[David_J_W · Accepted solution]

This is a system that is now approaching ten years old, so it is way past its design life and parts will not be available other than second-hand. Considering that there will be plenty of newer systems being given away or thrown away, it seems hard to justify spending any time on this one other than to recover any data on its hard disk (which is probably easiest done using a USB enclosure).

I'm unclear from your description whether the system is booting and working other than the internal display panel staying blank, or whether the system might not even be booting. If the system is booting but there is no display, my guess is that the screen backlight (or, maybe more likely, the inverter that powers the backlight) has given up. Be very careful if you go poking around in that part of the system, as high voltages are present. If the system is not booting, it could be anything but as you have tried different RAM and a different processor, I'd guess at a failed system board and/or display panel.

[ServiceShopKS]

It wasnt mine bc if it would be id throw it away as soon as id try 2-3 things.Also I know a lot about computers/laptops and voltages so I know how to work with electricity.But i still think its a BIOS problem.

-Thank You anyway

[David_J_W]

It sounds like you have done your best with this old system and have done way more than most people would. With these older systems the only sensible way sometimes is to abandon the failed hardware, recover whatever data you can and send the parts for recycling.