Hey, wait, before installing, we need to find out which version of Windows 7 to install, home version, professional version and flagship version. That is, turnips and cabbages have their own tastes, so I don't need to explain them to you one by one. Today, we will classify another version, that is, 32-bit and 64-bit versions directly related to computer hardware.
If you are an efficient spectator, please take the fast track to help you make up your mind, but if you want to have a deeper understanding of 32-bit and 64-bit, you might as well take the full track and read the whole article.
Fast track: If you are not keen on playing games at ordinary times, and your work involves a lot of development in a virtual environment, and you need a computer with more than 3GB of physical memory, try installing a 64-bit system. On the other hand, if you are a game enthusiast and don't need that much memory (3G memory can fully meet basic applications), try a 32-bit system.
Full channel: Why do we set the conditional threshold of memory to 3G in the fast channel? Actually, this has something to do with the 32-bit system architecture. Listen to me slowly.
The difference between 32-bit and 64-bit systems is really a long story. Here, we must first understand the architecture technology of CPU. Usually we can see X86 and X64 logos on computer hardware. In fact, these are two different CPU hardware architectures. X86 stands for 32-bit operating system and x64 stands for 64-bit operating system. So what does "bit" mean between 32 bits and 64 bits? Compared with 32-bit technology, this bit number of 64-bit technology means that the data width of CPU GPRS (general register) is 64 bits, and the 64-bit instruction set is an instruction to run 64-bit data, which means that the processor can run 64-bit data at a time. Give a simple but not particularly accurate example: the throughput of 32 bits is 1M, and the throughput of 64 bits is 2M.
64-bit computing has two advantages: it can be used for a wider range of integer operations; More memory can be supported. However, because of the change of numerical value, it cannot be simply considered that the performance of 64-bit processor is twice that of 32-bit processor. In fact, in 32-bit applications, the performance of 32-bit processors will be stronger, even for 64-bit processors, the performance is stronger in the current 32-bit applications. So don't be infatuated with 64 bits. 64 bits is not a legend. We should make a clear analysis before deciding whether to use 32-bit or 64-bit.
Are you a little confused? When to choose 64-bit and 32-bit? We will explain it to you in several parts.
Let me talk about memory first. Why can a 32-bit system only display 3G memory (actually 3.25G)? This is caused by the limitation of the system itself. A 32-bit system always has the ability to address the memory in 4G, and other things need to be put in 4G, such as the system BIOS, the addresses and settings of input and output devices, the settings and addresses of various interfaces, and so on. These addresses and settings occupy about 700M of space, so 4G memory can only display 32-bit 3G, but the remaining memory is not wasted.
So, is it true that a 32-bit system can't recognize 4G memory? Not exactly. We know that more than 700 MB of memory will be occupied by hardware addresses or interfaces, so can we use some means to make them occupy the space on the hard disk (similar to virtual memory) instead of physical memory, so that 4G memory can be completely recognized? Yes, this method is really feasible, so now there is a technology called PAE, which is called physical address extension in Chinese. This technology is provided on hardware devices, but it needs system support. For example, 32-bit Windows Server 2003 can support this technology well, but Vista's support is not very good. As for Windows 7, you can use it.
So I didn't say in the fast track that you must install a 64-bit system as long as it is larger than 3G memory, which depends on your actual work or use requirements.
In addition to memory, 64-bit technology is also related to hardware. Motherboards must first support 4G (some motherboards before 945 don't support 4G memory, so even a 64-bit system can't recognize 4G memory), and the processor (CPU) also needs 64 bits. Some people confuse dual-core and 64-bit CPU. Here I want to emphasize that dual-core and 64-bit are two different concepts. Dual-core means that there are two CPUs physically. Although 64-bit is a technology, it does not mean that it must be 64-bit as long as it is dual-core. For example, Pentium D series has 32-bit dual-core (at present, Core 2 dual-core is basically 64-bit), and there are actually two kinds of 64-bit, one is x64, which we often say, and the other is Intel's An Teng CPU, which is a 64-bit processor specially designed for large servers (the 64-bit client version cannot be installed at all, only the server version can be installed).
With the support of these hardware, you can start to think about using 64-bit system, but the most important thing is that we need to understand what risks 64-bit may have. Generally speaking, the following four questions should be considered.
1. Is there any better performance?
2. What is the compatibility?
3. How about reliability and safety?
4. Do you need to spend more money?
On the first question, we talked about it at the beginning of the article. Sometimes, a 32-bit system may perform better than a 64-bit system. We are used to inferring from experience that the performance of the computer has improved from 8 bits to 16 bits and from 16 bits to 32 bits. However, it is not easy to draw a conclusion about the performance improvement of 64-bit programs, because only 64-bit programs that have been optimized by 64-bit will have performance improvement. At present, most Windows applications have not been optimized, while 32-bit applications run on 64-bit systems.
Some people have seen a large number of 64-bit applications recently, but it should be noted that these applications are not to improve performance, but to solve the incompatibility problem of 32-bit programs on 64-bit systems. Of course, I believe there will be more and more such 64-bit optimization software. After all, 64-bit is the same direction, sooner or later.
The second question is very important. Compatibility is an important factor for a system to go to heaven or hell. In Windows 7, 32-bit system compatibility is excellent, but 64-bit system compatibility still has some risks. Although many softwares have been updated to be compatible with 64-bit versions, users still have to run a lot of 32-bit softwares on 64-bit systems, which may bring risks. In a 32-bit system, the DLL (dynamic link library) required for program running is stored under Windows\System32 of C:\, while in a 64-bit system, the 32-bit library is stored under Windows\SysWow64 of C:\. When a 32-bit program tries to load a library from system32, wow 64(Windows 64 Windows 64-bit) is responsible for redirecting it. Similarly, the program needs to be redirected when the registry is called. WoW64 redirects HKLM \ software to HKLM \ software \ wow 6432 node. Compared with other virtualization mechanisms, WoW64 can ensure software compatibility. Usually, these redirections work well, but any complex layer may lead to unforeseen problems, which are manifested as incompatibility. In addition, if you still have 16-bit software in your computer, it is definitely incompatible in a 64-bit system, which is also a problem that we need to consider in advance.
As for hardware compatibility, we can see from our previous tests that the overall hardware compatibility of Windows 7 is very good (about 90% hardware compatibility), but this refers to a 32-bit system. Under the 64-bit system, the current hardware compatibility is lower than that of the 32-bit system, but I believe this phenomenon will gradually improve with the development of 64-bit system.
Regarding compatibility, I recommend two addresses, a software compatibility list and a hardware compatibility list, which are very practical and officially provided by Microsoft.
/applications.aspx
/devices.aspx
The third question is about stability and security. In the 64-bit system, the security has been improved to a greater extent. PatchGuard (security kernel) and DEP (data execution protection) can protect the system from malicious acts such as buffer overflow attacks, but security cannot be solved by technology alone. In terms of stability, in theory, 64-bit stability should be better than 32-bit stability, but I have never experienced such a feeling when using it. The main problem is that the software and driver are incompatible, which may even lead to blue screen. Even if drivers are required to sign digital signatures, this phenomenon has not been greatly improved at present.
The fourth question, what are you most concerned about? I have a 32-bit system. Do I need to spend money to install a 64-bit system again? Friends who have bought the retail color box package (FPP) should know that in Windows 7, the 32-bit system and the 64-bit system use the same license when they are activated (that is, the key we often say), and the retail version usually contains both 32-bit and 64-bit media (it seems that the home basic version does not provide 64-bit media, but you can install it by downloading a 64-bit image), so you can decide which system to install. If you don't have 64-bit media, you can also contact your dealer to buy a separate media. However, it should be noted that the retail version can only install one system at a time. If you have activated your 32-bit system, you need to call Microsoft 800 to log off and then activate your 64-bit system.
With reference to the above four points, I believe everyone has a basic understanding of where to go. Let me sum up again, to realize real 64-bit computing, it is not enough to have a 64-bit processor, but also a 64-bit operating system and 64-bit application software. All three are indispensable, and 64-bit computing cannot be realized without them. In addition, we should also consider the reality, 64-bit is a trend, but now whether to experience it in person, we must make a good calculation. Of course, if you haven't made up your mind not to idle your computer, we can install 32-bit Windows 7 on 64-bit hardware to experience it, but if our hardware is 32-bit, it is absolutely impossible to install 64-bit Windows 7, which is the legendary "backward compatibility".