Absolutely not true. There is basically no performance benefit to be gained from 64bit in most situations and 64bit programs require slightly more memory than their 32bit pendant. Benefits to be gained from a 64bit OS: * The OS can fully use more than about roughly 3.5 (depending on the hardware) GB of RAM. * Small performance gains in very, very few highly optimized application (if you're asking yourself the question 32bit or 64bit than chances are you won#t be using any of those in the foreseeable future) Problems with 64bit OS: * Still lacking driver support, even years after the first 64bit Windows OS. If you are or plan on using any older peripherals like scanners, webcams etc. a 64bit OS is probably not for you. * Drivers have to be signed! * While you can use 32bit software, 32bit drivers are not compatible. * Incompatibility with older games and programs. Chances are pretty high that your old classic games will still work fine on Windows 7 32bit but refuse to work on Windows 7 64bit. * No 16bit emulation! You'd be surprised how many 32bit applications came wrapped in 16bit installers even a few years ago ... forget about using 16bit applications on your Windows 7 64bit. No problem with Windows 7 32bit. * Several drivers, even if they are available for 64bit, are still optimized for the 32bit versions of Windows making your 64bit version slower or less stable. If you have exclusively fairly recent hardware and more than 3gb of RAM or plan to upgrade to more than 3GB of RAM any time soon and you are not dependend on older software, than 64bits is for you. If not, 32bits will cause less hassle and problems. Simply upgrading from 32bit to 64bit or the other way round is not possible on Windows so make your decision wisely.
Ok. Install W7 64bits for normal use and XP 32bits for old old old old old old old applications/hardware that you have
I'm not sure if its your English skills that are letting you down but to me your performance benefits are baseless. No every day application benefits from a 64bit OS, programs compiled in 64bit actually require more memory, making the whole thing slightly slower. But either way, its negligible in both directions. Higher performance is not a valid selling point for a 64bit Windows, you won't be able to back up those claims, they are bogus.
Yes, or simply use W7 32bit and save you all that hassle. I just installed my antique Mustek scanner with its Windows 2000 drivers on W7 32bit and with some tweaking I can scan now. And I don't have to reboot or fire up a virtual machine any time I want to scan or play a not so old game. W7 64bit is a great OS, but if you aren't using more than 3.5 GB of RAM than it will still cause some headaches for absolutely no gain at all.
Look, I'm not generally speaking against W7 64bits, I'm just speaking against people like JouSePo who advertise it over the 32bit in any circumstances. I can not use the infamous, well integrated XP mode since my otherwise still more than capable Athlon 64 X2 Toledo does not support VT on my nForce4 board. Most owners of slightly more dated PCs and the majority of Note- or Netbook owners won't either. I can use VirtualBox to achieve a similar, maybe even better result (it supports DirectX and OpenGL support for guest systems and USB-pass-through), but system integration is still lacking. It's a minor inconvenience, but it is an avoidable one by simply using the flavor of Windows best suited to your hardware.
Or just use the complete XP 32 bit system, running in a virtual machine to run your old 32 bit and 16 bit applications. You can download it for free from Microsoft and configure it that way, your old software runs as usual on the vista Desktop, but in a virtual XP window. EDIT: OK, some other Guys were faster...
Does VirtualPC finally support 3D applications and USB-pass-through? If not it doesn't really solve most of your problems in addition of not being compatible with the majority of CPUs currently out there.
I would say, most CPUs in machines on which Windows 7 Professional, Enterprise or Ultimate are installed should support IVT or the AMD Pendant...