Unable to boot (3F0)

[15-da0061nf]

Hello everyone !

I recently upgraded my pc with more RAMs and I wanted to install my old RAMs in my girlfriend's HP pc. I thought they were compatible but it seems that my old RAMs frequency is too high for her pc.

The thing is, when I wanted to start her pc after putting the RAMs, I got an error saying "Boot Device Not Found. Please install an operating system on your hard disk. Hard Disk (3F0)".

So I switched back to her original RAM and restarted the pc, but I still got the error.

I did the quick and extensive check on the hard disk with F2, but it passed with no issue. Same for the memory card.

The hard disk was correctly detected in the BIOS, but it was not in the list for booting in UEFI mode. All I had with CD/USB drives boots and OS Boot Manager.

I tried switching to Legacy Mode since the hard drive was on this boot list. But it seems that it wanted to start on a Windows 7 version taht doesn't exist and I just got blue screened. So I went back to UEFI.

I remembered that I had changed her HDD for a SSD some years ago and that we had kept the HDD. So I got it and put it instead of the SSD, but I am facing the same issue.

I tried to reset the BIOS settings but it didn't change anything. I tried putting a version of Windows 10 on an USB drive and put USB drive first in the boot list, but it didn't boot on it. I then tried to press F11 to do the System Recovery but it didn't do anything and I keep ending on the same error page.

I have a hard time understanding how changing the RAM could cause such error. Maybe the RAM wrong frequency somehow messed up the pc ? I have checked everywhere but I have not found any solution. The only thing that I haven't done that I can think of is updating the BIOS, but I don't know if it will work.

Do you guys have any good idea ?

The model of the pc is HP 15-da0061nf.

[Hawks_Eye]

@15-da0061nf,

Welcome to HP Support Community.

Thank you for posting your query, I will be glad to help you.

It sounds like the system lost its boot configuration after the RAM swap. Here are a few things you can try to fix the Boot Device Not Found (3F0) error.

Check BIOS Boot Order Again

Since the SSD is detected but not in the boot list:

• Enter BIOS (F10 on startup)
• Go to Boot Order and make sure the SSD is listed.
• If it’s missing, try resetting Secure Boot and toggling between UEFI and Legacy.

Rebuild the Boot Configuration Data (BCD)

Since you tried booting from USB but it didn’t work, try again with these steps:

1. Create a Windows 10/11 bootable USB using the Media Creation Tool (if not already done).
2. Plug it in and press F9 at startup to select the USB manually.
3. Once in the setup, select Repair your computer > Troubleshoot > Command Prompt.
4. Enter these commands one by one:
   bootrec /fixmbr
   bootrec /fixboot
   bootrec /scanos
   bootrec /rebuildbcd
5. Restart and check if it boots normally.

Check if the SSD is GPT or MBR

• If you changed BIOS settings (UEFI ↔ Legacy), the drive partition type may not match.
• If your SSD is GPT, you need UEFI mode. If MBR, you need Legacy mode.

Update the BIOS

If nothing works, updating the BIOS may help, but it's risky if the laptop isn't booting. You can try downloading the BIOS update from another PC and flashing it using HP BIOS Update Utility.

Why did RAM swapping cause this?

It’s unlikely that the RAM itself caused damage. Instead, the system may have reset BIOS settings when it detected incompatible RAM, losing the boot configuration.

I hope this helps.

Take care and have a good day.

Please click “Accepted Solution” if you feel my post solved your issue, it will help others find the solution. Click the “Kudos/Thumbs Up" on the bottom right to say “Thanks” for helping!

Hawks_Eye

HP Support 

[15-da0061nf]

Hello Hawks_Eye and thank you for your answer.

"Check BIOS Boot Order Again"

SSD is still not in the boot list.

I had already tried Secure Boot and toggling between UEFI and Legacy but it didn't work. With Legacy it seemed to boot but on a non-existing Windows 7 version that just lead to blue screen.

"Rebuild the Boot Configuration Data (BCD)"

I did it but for "bootrec /fixboot" I got "Access denied".

With "bootrec /scanos" it found a Windows OS on the disk.

And with "bootrec /rebuildbcd" it asked wether to add it to starting list, I answered Y but it said that the system device cannot be found.

After that I restarted the pc but I still get the same error.

"Check if the SSD is GPT or MBR"

I tried both UEFI and Legacy mode, but none really works.

"Update the BIOS"

I updated it but I still get the same error.

[Hawks_Eye]

Hi @15-da0061nf 

We sincerely thank you for your patience and co-operation during this troubleshooting process.

I'm sending out a private message to assist you with the next course of action. 

In order to access your private messages, click the private message icon on the upper right corner of your HP Support Community profile, next to your profile Name.

Hope this helps! Keep me posted for further assistance. 

Please mark this post as “Accepted Solution” if the issue is resolved and if you feel this reply was helpful click “Yes”.

Take care, and have an amazing day!

Regards, 

Hawks_Eye