@Zucca it is meant to be >60 to kill off any germs (legionellas)
This was the card I was referring to. I am using it to check if the voltages are there. In modern mainboards it will not necessarily display the POST codes though.
@Tautech an old Haswell board may not be worth the effort. I'd throw out the battery and reset the cmos as it most likely got corrupted. You may want to check the mosfets for any shorts though, those are a common cause for failures.