Different Windows editions have had different upper maximum RAM limits. 64-bit Windows support different amounts of memory as an 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.
Read: Difference between 64-bit and 32-bit Windows.
Maximum memory (RAM) limits
So, while the maximum RAM limit for 32-bit Windows 7 / 8 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.
Maximum Memory limit for different versions of Windows 11/10
The maximum Memory limit for the different versions of Windows 11/10 are:
- Windows 11/10 Home: 128 GB
- Windows 11/10 Pro: 2 TB
- Windows 11/10 Pro for Workstations: 6 TB
- Windows 11/10 Education: 2 TB
- Windows 11/10 Enterprise: 6 TB
Here are the upper RAM limits for the different editions of Windows 7 64-bit:
- Starter: 2GB
- Home Basic: 8GB
- Home Premium: 16GB
- Professional: 192GB
- Enterprise: 192GB
- Ultimate: 192GB
These limits are similar to those for Windows Vista editions, except that Vista Enterprise and Vista Ultimate have had their upper limits raised from 128GB to 192GB.
Windows 8 and Windows 8.1, 64-bit has different memory limits depending on the edition.
- Windows 8: 128GB
- Windows 8 Professional: 512GB
- Windows 8 Enterprise: 512GB.
For Windows Server 2008 R2 Enterprise edition, the limit could extend to even 2 TB.
Will Windows 11 use more RAM?
There is no official statement regarding the usage of RAM by Windows 11. You can install Windows 11 on 4GB of RAM without any problem. Talking about the Memory consumption, you cannot say if Windows 11 consumes more or less RAM than Windows 10 or any other older version. It entirely depends on the number and weight of the apps and the settings you are using.
Hope this helps.