HP zbook 15 don't turns on

[Muhammad Irshad_1]

Hi Everyone
I have hp zbook 15 first generation. it is showing a strange when i try to turn it on , I press the power button, power button light turns on, but no display turns on, power button light stays lit for 5-6 seconds the it turns off and laptop dont boot.
When I place the laptop in really cool AC room for 1-2 hours then it turns on fine.
To overcome this issue I have tried following thins

• 
  got my laptop serviced fully (cleaned Fan, motherboad detached cleaned and reattached every component.
  Tried to remove mSata cards.
  Unplugged charger and battery and pressed power button for 45 seconds or so

All of these didn't solved my issue
Specs of laptop
Core i7 4800MQ
2 GB graphics cardNvidia Quadra 2100M (not sure on 2100)
16 GB RAM(1600 MHZ 2×8GB)
128GB mSata card containing windows 8.1 and kali linux in dual boot mood
I TB HDD 5500 RPM Toshiba

Thank you very much

 

[Laptop_Nerd]

Hi,

It seems like a hardware problem already, the GPU to be exact. Please do try these troubleshooting steps that may help.
- Start by doing a hard reboot, remove the battery and unplug the AC adapter then press and hold the power button for 20 seconds then try booting it up again.
- If this will not work, do test the AC adapter if it's working properly. Remove the battery and power the laptop with just the AC adapter connected and see if it will boot up or not. do also try a different AC adapter that has the same voltage and see if it will work or not.
- Proceed with reseating the RAM's if trying a different AC adapter will not work, remove them all for couple of seconds then put them back in making sure everything is seated properly.
- If it will still not work, connect an external monitor and see if you'll get any display from it. If there's a display on the external monitor that could mean that the problem is the built in display.
- But if there's still no display on the external monitor that means the problem lies in the GPU.