I would think Windows 8 would be 64bit only. MS can only hold people's hands for so long and we are looking at another 3 years until 8 comes out. Seeing as 64bit has been in the consumer market for nearly 8 years, i say in another 3 everyone will have a CPU capable of running 64bit. If not, then I highly doubt any of their components will be able to run Windows 8.
Windows Server 2008 R2 is the first Windows operating system to be offered for only 64-bit processors. And Windows Server 2008 R2 can now support up to 256 logical processor cores for a single operating system instance, including enhancements in Hyper-V virtual machines which are able to address up to 32 logical cores in a single VM. These improvements not only guarantee more bang for your server hardware buck, but also offer better reliability with fewer locks and greater parallelism.
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Crucial MX100 CT256MX100SSD1 256GB SATA III SSD (User Tree)
2 * Seagate Barracuda 7200.12 ST31000528AS 1TB 7200 RPM SATA II Mech. HD
Seagate ST1500DL001-9VT15L Barracuda 7200.12 1.5 TB S
Thermaltake Black Widow TX TR2 850W 80+ Bronze Semi-Mod ATX
ThermalTake Level 10 GT (Black)
Corsair H100 (CPU, dual 140 mm fans on radiator) + Air (2 * 210 mm + 3 * 120mm fans)
I know what you saying, they will still be around. But look at this way, people using XP that had 64bits or even 32bits, but had some really bad components couldn't run Vista even if the CPU could support it. I would think MS would finally figure it out by now. Windows 7 for instance is just like Vista for System Requirements, but those that are on XP that couldn't use Vista due to their lack of technology. There has to be a line. MS can't go holding people's hands that refuse to upgrade their components for 15years. That, or MS will start making software for certain OSes and up. In that case people will have to upgrade their system, which i bet 100% will be a 64bit CPU in some way or another.
I hope they make the switch on their primary OS to 64bit only.
I would not be shocked at all if it was 64bit only. Instead, I would be a little more put off by the idea that they are still wasting money working on hardware that will be very out dated. Already today it is probably nearing 50% of users have 64bit capable machines if not more, and it won't exactly be tomorow Win8 is released. Windows 7 was brought out quickly, more than likely to cover for Vista's failing sales and to recover their image on the market instead of getting further beaten on by Mac and other alternatives. I would not expect Windows 8 to be hitting the shelves for another 4 years from today at the earliest. At that point, 32bit hardware will be what... a decade out of date?
And as far as MS having just finally just 16bit, that is true. When however was the last 16bit operating system created by them? Dropping support is an entirely different concept than designing the core around. On another note, if 128bit tech is getting developed I hope MS doesn't waste time catching up. The Athlon64 series was released in 2003, and Windows XP x64 didn't release until April 2005. There is no way as large of a company as MS did not have access to the needed resources to be prepared in less than two years. They probably had prototypes available in 2001 or 2002 at the latest. If anything, they are to blame for the slow adoption of 64bit technology that even leads to us having to be curious about this kind of point.
Summed up : Windows 8 SHOULD be 64bit with compatability for 32bit code, and if it is on the market hopefully MS won't wait so long to begin 128bit (or whatever the next increment ends up being).