Well the PC is running Windows 8 Pro. I bought the upgrade downloadable version from microsoft.com without buying the installation media! The only way to re-download it again is to have another Windows OS already installed. I did some digging and there is an ESD directory that contains the downloaded components, but even with that the installer requires to "upgrade" a previous version of the OS.
If I want to use more than 4GB of ram, I have to install the 64-bit version of Windows 8. The installer will only do that if the previous Windows is already 64-bit!!! I didn't know any of that and so when I was upgrading, because I had Windows 7 32-bit, it got the 8 32-bit version instead, which is limited to 4GB
Thanks for letting me know about mactrackker, I am also quite shocked to find out there's a 2GB limit
... I'll probably upgrade the PC and maybe bump to Reason 6.5!
Thank you.. :-/