I'm using 2 GB RAM PC with core to duo processor .is Windows 8.1(64 bit) compatible with my PC or not??

Solution
Core 2 Duo chips should be 64bit compatible, but it's pointless to upgrade from 32bit to 64bit with that little memory.

At this point it's not worth upgrading core 2 duo computers at all, you can get a faster machine in the form of an intel compute stick, which costs only a little bit more than a retail copy of Windows 10!
Core 2 Duo chips should be 64bit compatible, but it's pointless to upgrade from 32bit to 64bit with that little memory.

At this point it's not worth upgrading core 2 duo computers at all, you can get a faster machine in the form of an intel compute stick, which costs only a little bit more than a retail copy of Windows 10!
 
Solution