I have NF7 that has been solid as a rock for a good 5years. Three days ago at start up it boots into the BIOS, with the following message "CPU is unworkable or has been changed". Did some research and it appeared to be a bad CMOS batt. So I changed it out and all appeared fine. Fired up the next morning and same issue, same message. I have found when it has been shutdown for 10-15 minutes it will happen.
I next was going to reflash the BIOS, but I noticed it still shows that date and version for the last update. Could the BIOS chip been damaged when the Batt died?

Thanks in advance,