Memory Limits for Windows and Windows Server releases

His topic describes the memory limits for supported Windows and Windows Server releases.

• Memory and Address Space Limits
• physical memory limits:windows 8
• physical Memory Limit S:windows server 2012
• physical memory limits:windows 7
• physical memory limits:windows Ser VER 2008 R2
• Physical memory limits:windows server 2008
• Physical Memory Limits:window S vista
• Physical memory limits:windows Home Server
• physical memory limits:windows server 2 003 R2
• Physical Memory limits:windows server 2003 with Service pack 2 (SP2)
• physical M Emory Limits:windows server 2003 with Service pack 1 (SP1)
• physical Memory limits:windows Server&nbs p;2003
• Physical memory Limits:windows xp
• physical memory limits:windows Embedded
• How Graphics cards and other devices affect memory limits
• Related topics

Limits on memory and address space vary by platform, operating system, and by whether theImage_file_large_address_awar E value of the loaded_image structure and 4-gigabyte tuning (4GT) is in use. Image_file_large_address_aware is set or cleared by using THE/LARGEADDRESSAWARE linker option.

4-gigabyte tuning (4GT), also known as application memory tuning, or THE/3GB switch, is a technology (only applicable to (+ bit systems) that alters the amount of virtual address space available to user mode applications. Enabling this technology reduces the overall size of the system virtual address space and therefore system resource Maximu Ms. For more information, see what is 4GT.

Limits on physical memory for 32-bit platforms also depend on the physical Address Extension (PAE), which allows 32-bit Wi Ndows systems to use more than 4 GB of physical memory.

Memory and Address Space Limits

The following table specifies the limits on memory and address space for supported releases of Windows. Unless otherwise noted, the limits in this table apply to all supported releases.

in on X86

Memory Type	Limit	Limit in 64-bit Windows
User-mode virtual address space for each 32-bit process	2 GB Up to 3 GB with image_file_large_address_awareand 4GT	2 GB withimage_file_large_address_awarecleared (default) 4 GB withimage_file_large_address_awareset
User-mode virtual address space for each 64-bit process	Not applicable	With image_file_large_address_awareset (default): x64: 8 TB Intel itanium-based Systems: 7 TB Windows 8.1 and Windows Server R2: TB 2 GB withimage_file_large_address_awarecleared
Kernel-mode Virtual address space	2 GB From 1 GB to a maximum of 2 GB with 4GT	8 TB Windows 8.1 and Windows Server R2: TB
Paged Pool	384 GB or system commit limit, whichever is smaller. windows 8.1 and Windows server 2012 r2:   15.5 TB or system commit limit, Whichever is smaller. Windows SERVER 2008 R2, windows 7, Windows server 2008, and windows vista:    Limited by available Kernel-mode virtual address space. Starting with Windows vista with Service pack 1 (SP1), the paged pool can also is limited by the pagedpooll Imit registry key value. windows Home Server and Windows server 2003:   530 MB windows xp:   490 MB	384 GB or system commit limit, whichever is smaller Windows 8.1 and Windows Server R2: 15.5 TB or system commit limit, whichever is smaller. Windows Server R2, Windows 7, Windows Server, and Windows Vista: GB or System commit limit, Whiche Ver is smaller Windows Server 2003 and Windows XP: Up-to-GB depending on configuration and RAM.
Nonpaged Pool	75% of RAM or 2 GB, whichever is smaller. windows 8.1 and Windows server 2012 r2:   RAM or TB, whichever is Smaller (address space is limited to 2 x RAM). windows vista:   Limited only by kernel mode virtual address space and physical memory . Starting with Windows vista with SP1, the nonpaged pool can also is limited by the nonpagedpoollimit regist Ry key value. windows Home Server, Windows server 2003, and windows xp:   % MB, or MB with 4GT.	Ram or GB, whichever is smaller (address space was limited to 2 x RAM) Windows 8.1 and Windows Server R2: RAM or TB, whichever is smaller (address space was limited to 2 x RAM). Windows Server R2, Windows 7, and Windows Server: 75% of RAM up to a maximum of GB Windows Vista: 40% of RAM up to a maximum of GB. Windows Server 2003 and Windows XP: Up-to-GB depending on configuration and RAM.
System Cache virtual address space (physical size limited only by physical memory)	Limited by available Kernel-mode virtual address space or the Systemcachelimit registry key value. Windows 8.1 and Windows Server R2: TB. Windows Vista: Limited only by kernel mode virtual address space. Starting with Windows Vista with SP1, System cache virtual address space can also is limited by the Systemcachelimit Regis Try key value. Windows Home Server, Windows Server 2003, and Windows XP: 860 MB with LargeSystemCache registry key set and with Out 4GT; Up to 448 MB with 4GT.	Always 1 TB regardless of physical RAM Windows 8.1 and Windows Server R2: TB. Windows Server 2003 and Windows XP: Up to 1 TB depending on configuration and RAM.

Physical Memory Limits:windows 8

The following table specifies the limits on physical memory for Windows 8.

Version	Limit on X86	Limit on X64
Windows 8 Enterprise	4 GB	GB
Windows 8 Professional	4 GB	GB
Windows 8	4 GB	GB

Physical Memory limits:windows Server 2012

The following table specifies the limits on physical memory for Windows Server 2012. Windows Server available only in X64 editions.

Version	Limit on X64
Windows Server Datacenter	4 TB
Windows Server Standard	4 TB
Windows Server Essentials	GB
Windows Server Foundation	Gb
Windows Storage Server Workgroup	Gb
Windows Storage Server	4 TB
Hyper-V Server 2012	4 TB

Physical Memory Limits:windows 7

The following table specifies the limits on physical memory for Windows 7.

Version	Limit on X86	Limit on X64
Windows 7 Ultimate	4 GB	192 GB
Windows 7 Enterprise	4 GB	192 GB
Windows 7 Professional	4 GB	192 GB
Windows 7 Home Premium	4 GB	+ GB
Windows 7 Home Basic	4 GB	8 GB
Windows 7 Starter	2 GB	N/A

Physical Memory limits:windows Server R2

The following table specifies the limits on physical memory for Windows SERVER 2008 R2. Windows SERVER 2008 R2 is available only in 64-bit editions.

Version	Limit on X64	Limit on IA64
Windows Server R2 Datacenter	2 TB
Windows Server R2 Enterprise	2 TB
Windows Server R2 for itanium-based Systems		2 TB
Windows Server R2 Foundation	8 GB
Windows Server R2 Standard	Gb
Windows HPC Server R2	GB
Windows Web Server R2	Gb

Physical Memory limits:windows Server 2008

The following table specifies the limits on physical memory for Windows server 2008. Limits greater than 4 GB for 32-bit Windows assume That pae is enabled.

Td>windows server 2008 Datacenter

Version	limit on X86	limit on X64	limit on IA64
Up GB	1 TB
Windows server 2008 Enterprise	Up to GB	1 TB
Windows server 2008 HPC Edition		GB
Windows server 2008 standard	4 GB	+ GB
Windows server 2008 for itanium-based Systems			2 TB /td>
Windows Small Business Server *	4 GB	GB	;
Windows Web Server $	4 GB	+ GB

Physical Memory limits:windows Vista

The following table specifies the limits on physical memory for Windows Vista.

Version	Limit on X86	Limit on X64
Windows Vista Ultimate	4 GB	GB
Windows Vista Enterprise	4 GB	GB
Windows Vista Business	4 GB	GB
Windows Vista Home Premium	4 GB	+ GB
Windows Vista Home Basic	4 GB	8 GB
Windows Vista Starter	1 GB

Physical Memory limits:windows Home Server

Windows Home Server is available only in a 32-bit edition. The physical memory limit is 4 GB.

Physical Memory limits:windows Server 2003 R2

The following table specifies the limits on physical memory for Windows Server 2003 R2. Limits over 4 GB for 32-bit Windows assume this PAE is enabled.

Version	Limit on X86	Limit on X64
Windows Server 2003 R2 Datacenter Edition	GB (GB with 4GT)	1 TB
Windows Server 2003 R2 Enterprise Edition	GB (GB with 4GT)	1 TB
Windows Server 2003 R2 Standard Edition	4 GB	Gb

Physical Memory limits:windows Server 2003 with Service Pack 2 (SP2)

The following table specifies the limits on physical memory for Windows Server 2003 with Service Pack 2 (SP2). Limits over 4 GB for 32-bit Windows assume this PAE is enabled.

Version	Limit on X86	Limit on X64	Limit on IA64
Windows Server 2003 with Service Pack 2 (SP2), Datacenter Edition	GB (GB with 4GT)	1 TB	2 TB
Windows Server 2003 with Service Pack 2 (SP2), Enterprise Edition	GB (GB with 4GT)	1 TB	2 TB
Windows Server 2003 with Service Pack 2 (SP2), Standard Edition	4 GB	Gb

Physical Memory limits:windows Server 2003 with Service Pack 1 (SP1)

The following table specifies the limits on physical memory for Windows Server 2003 with Service Pack 1 (SP1). Limits over 4 GB for 32-bit Windows assume this PAE is enabled.

Version	Limit on X86	Limit on X64	Limit on IA64
Windows Server 2003 with Service Pack 1 (SP1), Datacenter Edition	GB (GB with 4GT)	X64 1 TB	1 TB
Windows Server 2003 with Service Pack 1 (SP1), Enterprise Edition	GB (GB with 4GT)	X64 1 TB	1 TB
Windows Server 2003 with Service Pack 1 (SP1), Standard Edition	4 GB	Gb

Physical Memory limits:windows Server 2003

The following table specifies the limits on physical memory for Windows Server 2003. Limits over 4 GB for 32-bit Windows assume this PAE is enabled.

Version	Limit on X86	Limit on IA64
Windows Server 2003, Datacenter Edition	GB (GB with 4GT)	GB
Windows Server 2003, Enterprise Edition	GB (GB with 4GT)	GB
Windows Server 2003, Standard Edition	4 GB
Windows Server 2003, Web Edition	2 GB
Windows Small Business Server 2003	4 GB
Windows Compute Cluster Server 2003		Gb
Windows Storage Server 2003, Enterprise Edition	8 GB
Windows Storage Server 2003	4 GB

Physical Memory limits:windows XP

The following table specifies the limits on physical memory for Windows XP.

Version	Limit on X86	Limit on X64	Limit on IA64
Windows XP	4 GB	GB	GB (not supported)
Windows XP Starter Edition	Mb	N/A	N/A

Physical Memory limits:windows Embedded

The following table specifies the limits on physical memory for Windows Embedded.

Version	Limit on X86	Limit on X64
Windows XP Embedded	4 GB
Windows Embedded Standard 2009	4 GB
Windows Embedded Standard 7	4 GB	192 GB

How graphics cards and other devices affect memory limits

Devices has to map their memory below 4 GB for compatibility with Non-pae-aware Windows releases. Therefore, if the system has 4GB of RAM, some of it are either disabled or is remapped above 4GB by the BIOS. If the memory is remapped, X64 Windows can use this memory. X86 client versions of Windows don ' t support physical memory above the 4GB mark, so they can ' t access these remapped regio Ns. Any X64 Windows or X86 Server release can.

X86 client versions with PAE enabled does have a usable 37-bit (GB) Physical address space. The limit that these versions impose are the highest permitted physical RAM address, not the size of the IO space. That means Pae-aware drivers can actually use physical space above 4 GB if they want. For example, drivers could maps the "lost" memory regions located above 4 GB and expose this memory as a RAM disk.

Related Topics

4-gigabyte Tuning

Image_file_large_address_aware

Physical Address Extension

Original: http://msdn.microsoft.com/en-us/library/windows/desktop/aa366778 (v=vs.85). Aspx#physical_memory_limits_ Windows_8