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For users looking to switch to Windows 7, Windows 7 64 bit version is the version should be selected. But if not enough RAM (at least 4GB), or are using the hardware does not support 64 bit drivers, or need to upgrade from 32 bit to install the 32 bit version of Windows 7 might be the perfect choose more appropriate.
Some Windows 7 64 bit Windows XP Mode provides help solve some compatibility problems for applications, but it can not fix every problem. Here are some questions that users can not make the final choice.
A. Computer that supports Windows 7 64 bit?
Most computers made within 3 years (after Vista was released) will have the possibility to run Windows 7 64 bit. Except the computer using low-level CPU does not support 64-bit extensions of Intel or AMD. These types include CPU Atom CPU speed, and CPU Core (Core Duo, but not Core 2 Duo) Intel earlier. If uncertain systems using any type of CPU or CPU supports 64 bit operating or not you can use the free utility Intel Processor Identification Utility to check.
Two. Windows 7 that support the peripherals?
For computers that support, most peripherals are produced for Vista to work with Windows 7. However, the ability to support legacy hardware still can not confirm. Some vendors, such as providers Network Interface Card (NIC) or Disk Storage Controller (driver stored on disk) are more updated than the other vendors, so that the set peripherals are 64-bit computers using Windows Server versions from the period 2002 - 2003 support. These devices have no apparent ties to the data center (like the custom input devices, multimedia hardware, printers, ...) is difficult to be compatible because they are produced at the plant 64 bit is very rare. Ideally you should visit the vendor's Web site to check if the driver is 64 bit or not, or to find a solution to be able to use these devices.
3. Can use 32-bit device drivers in Windows 7 64 bit?
The answer is no. A device driver is code operating privileges in the same address space with the Windows kernel. So this driver should be in accordance with the structure of the nucleus. Some vendors have integrated both 32 bit and 64 bit driver for an installation package, and many users have 32 bit driver confusion that still work in Windows 64 bit operating system. However, while the 32 bit driver is not supported directly in Windows 7 64 bit, but users of Windows 7 64 bit still can install 32 bit driver in Windows XP Mode and use the printer or the USB connection USB devices connected to the other with Windows XP virtual machine.
4. Windows XP Mode is and how to use it?
The easiest answer is Windows XP Mode is a virtual machine that contains the Windows XP SP3 Virtual PC operating in Windows 7. This tool is free, the Windows 7 Pro, Ultimate and Enterprise editions can be downloaded here.
In essence, Windows XP is a 64 bit (actually a series of services and 64 bit drivers of devices) can generate 64-bit process modeled independent 32-bit PC environment.
Remember that Windows XP Mode limited to creating a virtual environment whether 32 bit Windows Virtual PC software platform is 64 bit and running in 64 bit version of Windows 7. So, while you can install Windows XP 32 bit (Windows Vista or Windows 7 32 bit or 32 bit) as a guest OS in Virtual PC in Windows environment (which is then a virtual machine with the possibility added compatibility for Windows XP Mode), then you can not install Windows XP 64 bit, or Vista or Windows 7 64 bit.
Five. Can run the 32 bit Windows applications in Windows 7 64 bit?
The answer is yes. Nearly all Windows 32 bit applications are supported on Windows XP can operate as normal on a Windows 64 bit. In doing so thanks to a tool known as the Win32 on Win64 (or WOW) to help move the Call (command applications use to request services) API from a 32 bit legacy Win32 applications Call the 64-bit API can be separate subsystem of the Windows 7 64 bit support. When the 32-bit applications will run stably on Windows 64 bit operating system, and now some of AMD and Intel CPUs have the ability to optimize the maximum speed. Some exceptions to the compatibility of WOW usually happens with other applications using one or more of the device driver 32 bit own heritage is inconsistent with the 64 bit version.
WOW concept is not new to the user. A similar tool is the first version of Windows NT used to support applications of the operating system Windows 3.xx 16 bit.
6. When installing 32 bit application in Windows 7 64 bit version can not see the Registry entries?
As noted above, the 64 bit version of Windows Vista and Windows 7 integration WOW class interpreter to operate the 32-bit applications. In addition to translating the Call API, operating system Windows 7 64 bit also isolates the changes in the Registry that the 32 bit application implementation and placing them in the key sub-groups particularly in the Registry accordingly.
For example, a 32-bit performance update a key in HKEY_LOCAL_MACHINE \ Software automatically saves its changes to the Wow6432Node key in the Software key. When expanding this key you will see all of the Registry key and value is the 32 bit WOW automatically.
7. Performance benefits when using the Windows 7 64 bit?
This depends on many factors. If you are working with large files or running applications that take up large amounts of memory, then Windows 64 bit version will bring some benefits over Windows 32 bit version running on the identical hard disk even when using 32 bit applications. This is because the operating system and device drivers also benefit from the large registers of the CPU 64 bit AMD or Intel when operating in 64 bit mode expansion. In addition, because Windows 7 64 bit version supports more physical RAM than 32 bit version of Windows 7 (192GB on all documents except copies of the 4gb Home with Windows 7 32 bit), you can easily extend the capabilities of PC using Windows 64 bit version.
8. Windows 64 bit operating systems use more RAM than Windows 32 bit?
Any 64-bit operating system will also take up more memory than 32 bit operating systems respectively. This is due to specific 64 bit code: This code uses the larger structures within it will occupy much more space, both on RAM and hard drive. And usually the ISO Image of Windows Vista and Windows 7 64 bit with a capacity greater than 50 to 70% of the 32 bit Image IO respectively, or use the Windows 64 bit physical RAM higher than 20 to 30% after launch.
9. Windows 7 64 bit more secure version of Windows 7 32 bit?
The answer is yes. Many improvements in Microsoft's widely introduced with Vista is only used for 64 bit versions, including Data Execution Prevention tool and hardware support PatchGuard. In addition, Vista and Windows 7 64 bit drivers should be required providers of encryption characters to prevent hackers and those who spread rootkits and set of tools such as the exploitation of the human driver .
10. Can I upgrade Windows 32 bit operating system to Windows 7 64 bit?
The answer is no. Upgrades Microsoft does not currently support the ability to move between the processor architecture. To upgrade from Windows 32 bit will have to install the new version of Windows 7 64 bit and then move all applications and data to the new operating system.