Is it necessary to reinstall Window when installing a new motherboard?

It is recommended to re install everything to avoid errors but you could just change them and hope it works without re installing

It works without reinstalling Windows, sometimes.

It depends on how similar the old and new hardware are to each other.

Yes it works sometimes, when changing from Intel to Intel,

but it still might give u errors and the performance will not be what is when new install is made.

Wait, so I need to re install every games to get the performance I want???
Dammit! I have too many games need to re install......
My internet connection speed is not so well, only 1mb/s......
Looks like I need to re download BF3 HUGE patch......

U can try, but the performance is imiss here.

Call your cable company and upgrade the speed to 25MB for a day or 2,

get it done and call back to resume the slower one : )

They will charge u only prorated price for the 2 days and back to normal when done : )

25MB!!!???
Nah, my country doesn't have this crazy internet speed......(the max is 5mb maybe)

Oh another question, I heard some people said that if your Windows was OEM, you were compulsory to re install your windows if you wanted to change your motherboard. Is that right?