HP Laptop 15da0073ms checksum BIOS reset..then goes thru diagnostics..all fail..never boots

[crossd]

the title says it all..i have found that there is no CMOS battery as the first message indicates the CMOS battery is dead..however on this model all is biult into the chipset..

so i need to replace the motherboard..is this Practical?  does HP sell replacement?  what cost?  it is just out of warranty

don

[Riddle_Decipher]

@crossd Due to the current global COVID-19 situation, we're seeing an influx of customers coming in for support and we appreciate your patience.

That said, during the startup process, the system performs a checksum test of the BIOS. If the checksum is incorrect, the BIOS is assumed to be corrupt and the system will install a hidden copy of the BIOS to correct the problem, and the startup process continues. The following message will be displayed for 15 seconds before the computer automatically reboots. You have the option of pressing Enter to proceed without waiting 15 seconds.

• The CMOS checksum is invalid.
• The CMOS will be reset to the default configuration and will be rebooted.
• Please check your BIOS Setup options to see if they changed.
• CMOS Reset (502)
• ENTER - Reboot the system

After the computer starts, a second message is displayed to indicate that the BIOS has been reset. This is an informational message and no additional action is required. However, if this error occurs more than once, there could be an issue with the installed version of the BIOS, and you should install an updated BIOS.

Install an updated BIOS

To resolve a BIOS issue, install the latest BIOS for your computer. See Downloading or Updating Software and Drivers for HP Computers for more information.

Refer to one of the following links for information about restoring the BIOS on your computer:

• HP Notebook PCs - Restoring the BIOS

P.S: Welcome to HP Community 😉

Let me know how that pans out, and if that doesn't work, we may need to replace the motherboard: click here for details on all your laptop's hardware components.

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That said, I will have someone follow-up on this to ensure you've been helped,

Just in case you don't get back to us, 

have a good day, ahead.