Boot Device Not Found after installing new RAM

[h1anna66]

I have HP Pavilion gaming 15-ec0007r. I have tried to update my RAM from 8 gb ( two 4gb sticks) to 16 gb (two 8 gb sticks, crucial 3200mhz). After installing new RAM my laptop says: CMOS Checksum is invalid, then reboots to a screen of "Boot device not found". Pressing ESC, F2 or F10 doesn't work. Installing one stick of RAM or old one results in the same Boot Device Not Found screen.

[Deep_World]

Hi @h1anna66,
 
Welcome to the HP Support Community!

Thanks for reaching out!

Sorry for the inconvenience caused don’t worry let me help you.

To better understand the issue, could you please provide a few more details?

• Did you disconnect the battery or power adapter before installing the new RAM?
• Have you noticed if the hard drive/SSD is detected in BIOS at all?
• Was the system working fine immediately before the RAM swap, with no boot issues?

Troubleshooting steps to try

1. Reset CMOS/BIOS
   • Disconnect the power adapter  
   • Hold down the power button for 15 seconds to discharge residual power.
   • Reconnect and try booting again.
2. Reseat the RAM
   • Remove both sticks, carefully reinstall them, ensuring they click firmly into place.
   • Try booting with just one stick at a time in each slot.
3. Clear NVRAM settings
   • If you can access BIOS (sometimes via F10 or F2 after repeated attempts), look for an option to “Load Setup Defaults” or “Restore Defaults.”
4. Check storage detection
   • If BIOS is accessible, confirm whether your SSD/HDD is listed. If not, the CMOS error may have reset boot order or disabled the drive controller.
5. Try old RAM again
   • Even if the error persists, this helps confirm whether the issue is related to the new modules or if something else was affected during installation.
6. BIOS update

• If possible, check HP’s support website for your Pavilion Gaming 15-ec0007r and see if a BIOS update is available. Sometimes newer RAM requires updated firmware support.

I hope this helps.

I'm glad I could help! 😊 If this resolved your issue, please mark it as "Accepted Solution" and click "Yes" on "Was this reply helpful?" Your feedback not only keeps us going but also helps others find the solution faster! 

Take care and have an amazing day ahead! 

Best regards,

Deep_World