3 light blinks on caps lock button, fans at max speed and no display.

[Astrooid]

I have an HP Laptop - 15s-eq0300ng with 8GB of 2666MHz RAM. I bought a Crucial CT16G4SFD8266 16GB stick to upgrade for my work. According to my research, the laptop supports up to 32GB of RAM and should work with 16GB dual-rank modules. However, after installing the new RAM, the laptop shows no display, and the Caps Lock blinks three times. The RAM is brand new, and I’ve previously used a 16GB stick that worked fine. I waited 10 minutes as some users suggested, but nothing changed.

I installed the RAM correctly and I’m 100% sure it doesn’t need reseating or cleaning. The slots are working fine, and I unplugged the battery before upgrading and followed all the proper safety steps. does anyone knows how to fix this problem?

Does anyone know how to fix this?

[Kuroi_Kenshi]

Hi @Astrooid,

Welcome to the HP Support Community!

Thanks for reaching out!

We're thrilled to have the opportunity to assist you and provide a solution.

I understand your HP 15s-eq0300ng laptop shows 3 blinks on the Caps Lock, fans at max speed, and no display after installing a new 16GB RAM stick. Let’s go through detailed troubleshooting steps.

1. Understand the Error Code

On HP laptops, 3 blinks on Caps Lock usually indicate a memory (RAM) error.

This means the system is not recognizing the new RAM module correctly, even if it’s physically seated properly.

2. Check RAM Compatibility

Confirm the Crucial CT16G4SFD8266 matches your laptop requirements:

DDR4 SODIMM

2666 MHz (matches your original RAM speed)

Voltage compatible (typically 1.2V for DDR4)

Some laptops are sensitive to single-rank vs dual-rank modules, even if officially supported.

3. Test RAM Individually

Remove the new 16GB stick.

Insert only the new RAM in Slot 1.

Try to power on.

If 3-blink error persists, the RAM module may be incompatible or defective.

If it works, try adding the original RAM in Slot 2 and test dual-channel mode.

4. Reset BIOS / Clear CMOS

Turn off the laptop and unplug all power sources.

Remove the main battery (if removable) and hold power button for 15–20 seconds.

Reinstall battery and power on.

This clears residual power and may help the laptop detect new RAM.

5. Check BIOS Version

Some HP 15s laptops require a BIOS update to support higher capacity or newer RAM modules.

Check your current BIOS version: Power on → press Esc → F10 for BIOS Setup.

Compare with the latest version on HP 15s-eq0300ng Drivers & BIOS.

If outdated, update BIOS using your original RAM installed.

6. Swap Slots

Some laptops are slot-sensitive:

Try the new RAM in Slot 2 instead of Slot 1.

Test with only the new RAM installed to see if it posts.

7. Check for Defective RAM

Even new RAM sticks can be faulty.

If possible, test the Crucial 16GB stick in another compatible laptop to verify functionality.

I hope this helps.

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