Was the battery brand new Zeld? Normally CR2025 or CR2032 3v. The exact voltage is important. Use a multimeter if you can. Make sure the base of the battery is making contact, and the side metal clip is touching the side of the battery firmly. It's possible that these connections could be broken or corroded, and the
RAM part of the CMOS is no longer receiving power, or may no longer be able to save it's data any more.
I've checked out your motherboard. Some motherboards have an external 3/4 pin connector you can connect an external battery to in the event the onboard one is no longer functioning, but the board does not have this facility. Nor can the CMOS be removed and replaced, by the looks of it is also soldered to the board. In this case, if the problems are hardware related, then the only option would be to replace the board
