It can be useful to first check details of existing Windows operating system and if a 64 bit OS can be installed on a PC (especially for older hardware) before starting off the installation.
Determining the current version of Windows installed can be done directly without any external tool by accessing Windows Settings (Windows key + X > Settings).
It however won’t check for hardware compatibility with 64 bit OSes. 64bit Checker is a free tool that will quickly show if this can be done and also display the details of current version of Windows.
Download it from here. This is a portable tool with no installation needed. So simply download and run it.
It will display the details of existing Windows and whether a 64 bit OS installation is supported or not.
These details can also be saved as a report either as a text file or a HTML document.
The generated report can then be saved for reference.
All done.