RTC Battery change before it's too late.
Remove old battery. If possible Cut legs with pliers or cutters or what ever and use soldering iron to gently remove the rest.
Connect new battery to these pins. Polarity is important.
New battery socket is not same size and doesn't fit in directly so you need to improvise and use jump wire.
I soldered (+) straight to the motherboard and (-) with jump wire.
I could have put battery socket flat to the board and solder (-) wire from the other side but then the memorycard wouldn't fit in to the expansion slot.