Learn how to fix computer error "System hardware does not match CMOS configuration".
For some reasons, the BIOS has identified different hardware than that listed in the CMOS setup, or the CMOS RAM contents have been lost.
Start by checking your CMOS RAM contents through the CMOS setup routine. Make sure that the CMOS setup is configured correctly. Configuration errors can frequently happen when new drives or RAM is added to the system.
Remember to contents won't hold, check the battery connector to see that the battery is secure. A loose or corroded battery connector might effectively. Disconnect the battery; even if the battery is working properly.
If the CMOS RAM contents still don't hold, you should replace the CMOS backup battery outright. When replacing the battery, be sure to install the new battery in the proper orientation, and verify that it is secure in its connector.
By taking the above steps, you would be able to fix the error, "System hardware does not match CMOS configuration."
This error often happens when RAM is added to the system; even though there is no entry for installed RAM anywhere in the CMOS setup. Try to "exit saving changes"; even though you might not have changed any settings.