Unable to save bios setting


Aug 2, 2015
I screwed up big time i think. My friend's cpu would start when he plugged in the cpu even without switching on the button on the cpu itself and would tk u to the bios screen. I did my own research (also on tomshardware). I found that in bios setting the power was set at "last state" so changed it to "stay off". Another problem was post every power boot the date would revery back to 2002 so changed that too to the current date.
Now the problem - when the above is saved and when i powered up pc the same issue and when checking the bios none of changes have been saved. And the power option and date show as "last state" and 2002 respectively. Again i checked on few blogs and found that the battery may b the problem so opened the cpu to find out the battery model i removed it when my friend plugged in the cpu remember the battery is still out. As usual the cpu starts but then nthng comes up.on the screen. Now we dont even hv a display with battery in. Plz assist

without the cmos coin battery (or sufficient voltage) the date/time and hard disk configuration and CPU configuration are lost when powered off

disconect from mains
(psu provided power to motherboard even when Windows shuts down PC)
refit new battery
reset cmos using jumper method

go into bios
to load defaults
reset date time
[check setting for power failure]

hopefully it will now work correctly

Mike Barnes