Laptop black screen when switched on ,also fan noisely and blinck three time caps lock and num lock

[1765swai]

Suddenly i power on ,don't boot in windows 10, remain black screen. I have tried different way to solve such as replace ram into different slot ,remove CMOS battery and put it again,plug a.c adapter for 2 hours ,but none of them solved. Blink three caps lock and num lock

[praveen196]

@1765swai Welcome to HP Community!

I understand that the laptop screen is black while turned on.

Do not worry. I will try to fix the issue.

Please perform the hard reset and check.

1) Shutdown the computer.  

2) Unplug all the Adapter and peripherals connected.  

3) Remove the Battery. ( not for Built-in Battery computer ) 

4) Press and hold down the power button for 15 to 20 seconds.  

5) Plug-in the Adapter and put the Battery back into the computer if it's a (removable battery)

6) Try to turn on the computer and check, If the issue persists continue next step

Please, review this HP article in an attempt to fix the issue >> https://support.hp.com/us-en/document/c01732674

Based on your description it should be failed BIOS upgrade. However, 3 blinks mean memory issues.

Check this article, as well >> https://support.hp.com/nz-en/document/c02693833

and perform Step 3 and try the USB pendrive BIOS recovery method.

Keep us posted,

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Give us a virtual high-five by clicking the 'Thumbs Up' icon below, followed by clicking on the "Accept as solution" on this post, 

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