What is the maximum memory (RAM) limit for 64-bit Windows 7 ?

[Nibiru2012]

This article is several months old, but I found it to be useful and informative.

By Windows Club | September 6th, 2009

Different Windows editions have had different upper maximum RAM limits. 64-bit Windows support different amounts of memory as a SKU-differentiating feature, with the low end being 512MB for Windows XP Starter to 128GB for Vista Ultimate and 192GB for Windows 7 Ultimate.


All 32-bit Windows client SKUs, however, including Windows Vista, Windows XP and Windows 2000 Professional, support a maximum of 4GB of physical memory. 4GB is the highest physical address accessible with the standard x86 memory management mode. Hardware Specifications for Windows 7 lays down the minimum memory (RAM) requirements.


So, while the maximum RAM limit for 32-bit Windows 7 editions is 4GB, when it comes to the 64-bit editions, the amount of memory that the OS can address depends on which edition you are running.

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Here are the upper RAM limits for the different editions of Windows 7:

Starter : 2GB
Home Basic : 8GB
Home Premium : 16GB
Professional: 192GB
Enterprise : 192GB
Ultimate : 192GB​

These limits are similar to those for Vista editions, except that Vista Enterprise and Vista Ultimate have had their upper limits raised from 128GB to 192GB.

SOURCE

 

[clifford_cooley]

One should also note there is hardware limits. Max memory per slot on the motherboard.

Unless I am badly wrong it would take a server type motherboard to enable memory over 24GB (6x4GB).

 

[Nibiru2012]

You ARE correct. I just thought is was an interesting article.

But then again, nearly all users don't need more than 6GB of RAM anyway.