Partition 1 has Win XP & Partition 2 has Windows -7 ( 32 bit ) ( Ultimate Version ) I am getting a new machine with i-7 Processor & 12 GB RAM, 1 GB ATI Video card & 500 GB HDD. Can I format the Win XP partition & install 64 bit version of Windows 7 & use that HDD in new machine by booting 64 bit version ? Meaning can I have both 32 bit & 64 bit versions of Windows -7 in 2 different partitions on the same HDD so that I can use that hard drive in both machines, the old and the new ? That way I can boot 32 bit when I put that HDD in old M/C and boot 64 bit when I use the same HDD in new Machine ? The reason is this : I have Five 500 GB internal HDDs. Currently in my old machine I have 2 drive slots & I clone my HDDs twice a week as a back up. In my new machine there is only one slot & since all of my HDDs are internal, I can not clone them in new machine. So I will be using old machine just for clonning HDDs twice a week. Sounds crazy but I will appreciate all Ideas. By the way XP Partition is Primary & I will be installing 64 bit Win 7 in Primary partition. Will that make any difference ? I do have Acronis Disk Director to make any changes required. Thank You.