winxp 为什么只能支持3.3G内存

junhn.yang

经测试
操作系统或是主板实体显示上可能都会告知内存只能侦测到3.12 GB～3.3GB之间的物理内存容量，
此问题我想发生的因素包含着2个主要原因：硬件芯片组支持与操作系统软件的限制。也不知对不对.但如果是对的,就对是对的,但我也不知原因何在,希望牛人指点一下.

aaaaa5aa

操作系统软件的限制，一般只识别3G左右的内存，如果你换为64位的系统，将会识别更高的内存

unixlinuxsys

Operating system support

[edit] FreeBSD

FreeBSD supports PAE in the 4.x series starting with 4.9, in the 5.x series starting with 5.1, and in all 6.x and later releases. The kernel PAE configuration option is required. Loadable kernel modules can only be loaded into a kernel with PAE enabled if the modules were built with PAE enabled; the binary modules in FreeBSD distributions are not built with PAE enabled, and thus cannot be loaded into PAE kernels. Not all drivers support more than 4 GB of physical memory; those drivers won't work correctly on a system with PAE.[2]

[edit] Linux

The Linux kernel includes full PAE support starting with version 2.6,[3] enabling access of up to 64 GB of memory on 32-bit machines. A PAE-enabled Linux-kernel requires that the CPU also support PAE. As of 2009[update][citation needed], many common Linux distributions come with a PAE-enabled kernel as the distribution-specific default[4] even though it does add overhead, it also adds the NX bit [5] .

[edit] Mac OS X

Mac OS X for Intel Macs supports PAE and the NX bit on all CPUs supported by Apple (from 10.4.4—the first Intel release—onwards). Mac Pro and Xserve systems can currently support 32 GB of RAM, even though the Mac OS X 10.5 Leopard kernel remains 32-bit. [6]

[edit] Microsoft Windows

PAE is supported in the following 32-bit releases of Microsoft Windows:[7][8][9][10]
Version         Maximum Physical Memory (RAM)
Windows 2000 Professional, Server         4 GB
Windows 2000 Advanced         8 GB
Windows 2000 Datacenter         32 GB
Windows XP Starter         512 MB
Windows XP Home & Professional (32-bit)         4 GB
Windows XP Professional - Media Center (32-bit)         4 GB
Windows XP Professional (64-bit)         32 GB
Windows Server 2003 Web         2 GB
Windows Server 2003 Standard, Small Business/Home, Storage         4 GB
Windows Server 2003 Enterprise Storage         8 GB
Windows Server 2003 Enterprise         32 GB
Windows Server 2003 Enterprise R2/SP1, Datacenter         64 GB
Windows Server 2003 Datacenter R2         128 GB
Windows Vista Starter         1 GB
Windows Vista Home Basic, Home Premium, Business, Ultimate, Enterprise         4 GB
Windows Server 2008 Standard, Web         4 GB
Windows Server 2008 Enterprise, Datacenter         64 GB
Windows 7 Ultimate 32 bit         4 GB
Windows 7 Ultimate 64 bit         64 GB? (TBC)

Windows XP Service Pack 2 and later, by default, on processors with the no-execute (NX) or execute-disable (XD) feature, runs in PAE mode in order to allow NX.[11] The NX (or XD) bit resides in bit 63 of the page table entry and, without PAE, page table entries only have 32 bits; therefore PAE mode is required if the NX feature is to be exploited. However, desktop versions of Windows (Windows XP, Windows Vista) limit physical address space to 4 GB for driver compatibility reasons.

[edit] Solaris

Solaris supports PAE beginning with Solaris version 7. However, third-party drivers used with version 7 which are not specifically written to include PAE support may operate erratically or fail outright on a system with PAE.[12]

unixlinuxsys

Windows XP Home & Professional (32-bit)         4 GB
Windows XP Professional - Media Center (32-bit)         4 GB
Windows XP Professional (64-bit)         32 GB

要修改PAE

lsw

4GB没问题

kot

这种问题似乎发错地方了——当然，发到存储或者AIX版面就更不对了

beyondfly

Windows XP Starter

还有这个版本啊

aaaaa5aa

64位系统就会认出4G以上内存

whenmind

俺只知道2003 ENTPRISE 32 R2 支持32G
64位的话，好像更多

shengchuang

修改PAE