CMOS battery not working and CPU fan sensor not detecting fan.

I recently got a motherboard (second hand) and all is working well except three things:
The BIOS battery doesn't seem to work.
The CPU fan doesn't show proper temps or speeds in BIOS.
And the PSU voltage rails are showing weird voltages.
I recently found that the motherboard didn't have a jumper on the bios pins so I put it on 2-3 (normal on my mobo) and it still doesn't seem to work after replacing the battery.
The next thing is that in the BIOS the temps are shown as 1 degree Celsius and the fan speed as 0 RPM. Lastly, the rails are showing weird voltages (16v on 12v rail etc) and I would really like to get these fixed, could someone please help me out?
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More about cmos battery working sensor detecting
  1. Broken board bad PSU? Those are the questions you need answered. Most importantly you need to know if the PSU is really sending out +16volts instead of +12. A multimeter would be able to measure that in a spare molex.
  2. Hi, thanks for the reply. The PSU is a 400w CoolerMaster that I got 2 years ago and has just started showing these voltages since I changed mobo. I read once, if a mobo would ever reach 16v, it would shut itself down to prevent damage, but the board seems fine.
  3. By your description it sounds like the board is bad. It is important that you check with the motherboard manual that you have that jumper you added in the right spot.
  4. Yes, little diagram in white showing where the jumper should be, I placed it in the appropriate position.
  5. Try reflashing the bios.
    Is that feasible?
  6. Sorry to sound like a newbie, but how do I do that?
  7. Check the motherboard manual or the manufacturer of the motherboard's website.
  8. Ok, I reflashed the bios with the latest version (was already the latest), and it is still showing the same things in the bios sadly :(
  9. bump
  10. bump
  11. Bad board!
  12. OK, I think I can live with it though.
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