How much physical memory can a 32-bit operating system use?

Link: http://www.cnblogs.com/hokyhu/archive/2010/04/30/1724597.html

 

Operating System
The physical memory ceiling actually supported by the system is determined by three factors:

CPU, motherboard, and operating system itself.

32-bit operating systems are generally
Yu

X86 architecture

CPU design,Traditional

Maximum x86 CPU support

232

Bytes

4 GB

Memory

. However, the current

X86 CPUs are generally supported

PAE mode, enabled

Theoretical support for the PAE Model

64-bit physical addressing, that is

264

Bytes,
However, for performance, cost, and other reasons

PAE is only extended

36-bit physical addressing, soCurrently, most

CPU support

236

Bytes

64 GB

Physical memory

.

Motherboard restrictions generally refer to the motherboard description
The maximum supported physical memory is clearly indicated. This restriction is generally affected by the motherboard address bus, chipset, and production costs.

Finished

CPU and motherboard, and then back to the operating system itself.Vast majority

The 32-bit operating system supports

4 GB

Memory

, With only a few exceptions, such

Windows XP
Stater supports up

M memory, mainly for product positioning considerations.

To support
Greater

4 GB memory, which must be supported by the operating system

PAE

Mode.

Because

PAE mode and

No PAE Mode
Although the formula is generally compatible, it is still somewhat different, so the previous driver can normally support

PAE is relatively small, so most operating systems are disabled by default.

PAE mode.

Even
Enabled

PAE, not all supported

64 GB

Memory

, Some

8 GB, some

16 GB ......I
This is because most systems do not actually use such a large amount of memory. If too much memory is supported, it will consume a lot of memory for memory management. On the other hand, there may also be considerations for product classification positioning.

The following lists common

32

Bit Operating System

Maximum memory supported.

Operating System	Maximum memory (GB)	Remarks
Windows 2000 Professional, Server	4
Windows 2000 Advanced Server	8	PAE
Windows 2000 datacenter	32	PAE
Windows XP Starter	0.5
Windows XP Home & Media Center	4
Windows XP Professional	4
Windows Server 2003 web	2
Windows Server 2003 small business, home, storage	4
Windows Server 2003 enterprise storage	8	PAE
Windows Server 2003 Standard (SP1/SP2/R2)	4
Windows Server 2003 Enterprise (SP2)	64	PAE
Windows Server 2003 datacenter (SP2)	128	PAE Special server configurations are required
Windows Vista starter	1
Windows Vista Home Basic	4
Windows Vista Home Premium	4
Windows Vista Business, enterprise, ultimate	4
Windows Server 2008 standard, web	4
Windows Server 2008 Enterprise, datacenter	64	PAE
Windows 7 starter	2
Windows 7 Home Basic	4
Windows 7 Home Premium	4
Windows 7 Professional, enterprise, ultimate	4
Versions earlier than Linux kernel 2.3.23	4
Linux Kernel 2.3.23 and later versions	64	PAE
Versions earlier than Mac OS X 10.4.4	4
Mac OS X 10.4.4 to the current version	32	PAE