Laptop doesn't switches on, shows black screen. Caps lock LED blinks twice in sequence.

[HSS68]

Power connected to the laptop. 
After start-up you can hear the fan/ dvd with still black screen.

Caps Lock led blinks 2 x long white (2 Hz), no sound. 
Black screen. 

[Hawks_Eye]

Hi @HSS68 

Welcome to the HP Support Community! 

Thanks for posting your query! We're here to help you get back up and running.

The issue you’re describing with your HP ENVY Notebook—black screen, 2x blinking Caps Lock LED, and no sound—indicates a hardware issue, possibly related to the system board, memory, or display. 

Let’s try some troubleshooting steps to isolate the problem:

 

Step 1: Perform a Hard Reset

Turn off your laptop and unplug the power cord.

Disconnect all peripherals (e.g., mouse, external drives, etc.).

Press and hold the Power button for 15 seconds.

Reconnect the power cord and turn the laptop back on.

 

Step 2: Check the Meaning of the Blink Code

On HP laptops, the blink pattern of the Caps Lock light often signals a specific error. For 2x blinking, it’s typically associated with memory (RAM) failure.

To verify, consult HP’s official LED Blink Codes documentation for your model.

 

Step 3: Reseat the RAM

If you’re comfortable opening the laptop:

Turn off the laptop and unplug it.

Remove the back panel and locate the RAM modules.

Carefully remove the RAM sticks, clean the contacts with a soft eraser or lint-free cloth, and reinsert them.

Ensure they’re securely seated in their slots.

 

Step 4: Connect to an External Monitor

Plug the laptop into an external display to check if it’s a display issue.

If the external monitor works, the problem is likely with the internal display or cables.

 

Step 5: Run HP Hardware Diagnostics

Turn off the laptop.

Turn it back on and immediately press the Esc key repeatedly until the startup menu opens.

From the menu, choose System Diagnostics > Component Tests and run a memory test.

 

Step 6: Update or Reset BIOS

A corrupted BIOS can cause startup issues. Visit the HP Support website on another device to download the latest BIOS for your model and follow instructions for updating or resetting it.

How to Reset BIOS Settings: A Step-by-Step Guide | HP® Tech Takes

How to Update BIOS Software on Windows PCs | HP® Tech Takes

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Take care, and have an amazing day!

Regards, 

Hawks_Eye