I have been trying to do BIOS recovery on dell Inspiron 14 5480 following the content below.

https://www.dell.com/support/kbdoc/en-th/000132453/how-to-recover-the-bios-on-a-dell-computer-or-tablet

however it doesn’t work. Here is my status.

1. I push ctrl+esc then plug-in. The screen is black with 3, 3 flash light on plug-in light (I google it, it means I don’t have recovery file)

2. I download and rename BIOS_IMG.rcv and place it in usb, but it still doesn’t work, black screen with 3,3 flashing light

3. I also tried this link, but the command line in the link doesn’t work for me (C:\\ /writehdrfile /writeromfile)

https://www.dell.com/support/kbdoc/en-th/000130691/bios-recovery-steps-for-a-no-post-issue-on-alienware-aurora-r5-r6-r7-r8-r9-r11-and-xps-8910-8920-8930-pcs

Now I wonder if I could download BIOS recovery from dell website for Inspiron 14 5000 or contact dell support is the only option for me since the first link doesn’t mention Inspiron

Please help, thanks.

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My pc is dell inspiron 14 5000 (5480) mfg year 2019 with OEM window 10

Additional info, I tried to format and reinstall window to reallocate disks space and partitions, but I messed up and delete everything (including recovery data for factory reset, I think). I somehow manage to install window with recovery window download to usb but couldn’t boot it (no bootable device found problem). I tried to fix it in BIOS setting and here I am.

Please help me. Thanks