Really sirious problem,my pc wont turn on

With system off, remove the motherboard battery for a few seconds, and reinstall. Resetting the bios will sometimes work. Also check for leaks with your water cooler.

It could be that your PSU is failing and doesnt supply enough voltage. How old are the PC / Components ?

ulysses35 :

the pc is about two and a half years old,and i tryed replacing to a different PSU,and still it doesnt work.

o1die :

i think that removing the BIOS battery is the only thing i didnt do,and i didnt do it because i didnt do any changes at all in the bios,no overclocking,no nothing...
do you think that it could be the problem even though i didnt do any changes there?

i'll check for leaks,even though i didnt see any water any where,do you think a leak in the water cooling system could prevent the pc from starting at all ??
i think it would start but then it will turn off because the CPU will reach an extreme heat,it happened to me with my last pc,i didnt have enoghth thernic solution on the CPU.

the thing was that,it turned on but got stuck in the BIOS screen,after figuring that it wont continiue,i made a restart,and then it just didnt turn on.

at the moment it happend i opened the PC and started removing components,and while doing that i didnt see any water any where,but,i think that it will be a good idea to replace the pipe after 3 years.

you know what i will never use water cooling again...enoghth to have one little hole in the pipe and all your pc can burn....i think thats the problem,the mother board got water on it,and it just got burned...