CMOS checksum invalid. CMOS 502 Error.

[liquidwax]

Product name: HP ENVY TS 15 J127TX Touch Notebook PC

Product number: F7Q47PA#AB4

BIOS Version: F.56

OS: Windows 8.1

It happened after a BIOS update which had resulted in the laptop not booting. A successful message was displayed instead. The BIOS version is F.56 and is currently the latest on the support page. Ironically, the description says the update "Fixes an intermittent issue where the system does not restart the operating system properly after the BIOS is upgraded." The capslock LED would flash twice and refuse to start. Suggestions I got from forums were to reset the CMOS. 

What I did:

1. Remove the flat battery and waited a while before I re-inserted it.

2. Held down the power key for 30s.

3. Connected to cord and powered up.

The laptop was fine for 2 weeks till Windows got stuck in a repair loop. I had to refresh Windows to get it to boot. I had also restored from a system image I did with Paragon HDM and no problems for another week.

For no apparent reason, the CMOS error was displayed few days ago. There were also no  changes made to the system.

I've tried many times to reflash again and followed by a hard reset after each of them with no success. I've also replaced the battery even though I didn't think it would be flat so quickly for a 6-month old laptop.

Questions:

1. Would a reset to factory default restore a working BIOS?

2. Would the "Rollback" feature in "Firmware Management" in Diagnostic be sufficient instead?

3. I did attempt to do a "Rollback" but there was no firmware found. I explored the recovery partition and  the folder labeled as "previous" under the "Bios" directory  was indeed empty. Would the "Rollback" work if a good firmware is copied to the folder? What are the files to use and how do I get them?

A factory reset is the last thing I want to do so please advise if there are other options.

"If it's ain't broke, don't fix it".

PS. I had  initially sent this using the "Contact HP" page but received a reply informing me that there's no email support for my laptop. Why didn't it stop me before I wasted my time typing the message? 

[CherylG]

Go to your drivers page and locate Bios update. In the description there should be a link to "Previous versions". Click that and you will see all versions posted. Download and run the last one before F.56.

[liquidwax]

Yes, previous versions "should" be provided but not there.

Bios Page

I've created recovery discs (total 5), would i be able to find it there?

[liquidwax]

This is ridiculous. Is there not a single HP employee who can provide me the bios version before F56?

Or anyone from the community? I've searched through the HP ftp for 2 hours and found nothing. Since they are labeled as spxxxxx, it would help if anyone could tell what spxxxx was for the version before F56.

[CherylG]

I have searched through most models in the Envy 15 J100 series. All list only BIOS F.56 for download.

Since it is a weekend there are not likely to be any HP employees online here. Maybe Monday.