I have just got new computer with win7 professional 32 bit. It is capable of supporting 64 bit. What options do I have to upgrade to win7 64 bit. Many thanks for any advice
You have to do a fresh install from scratch using the provided 64bit disc. If you don't have the disc just call Microsoft and they can mail you one. You have the license you're just buying the disc. There is no other way.
32-bit OSes are limited to 4GB in theory, in reality more like 3.25GB system RAM. You're definitely limiting yourself with a 32-bit OS. I've been using 64-bit myself for a while now, at first with 4GB RAM, now 8GB, and there are no compatibility issues.
I find it strange that any computer manufacturer would supply a computer with 8 Gig of memory and only install a 32 bit operating system. Furthermore most computers you buy in computer stores and by mail order have all got Windows 7 64 bit installed on them regardless of the amount of memory installed. Are you sure that you are running 32 bit Windows 7? To check simply do properties of “Computer” on the start menu.