Max RAM for Windows 98 SE - TechRepublic.
Certain 32-bit versions of Windows Server running on x86-based systems can use PAE to access up to 64 GB or 128 GB of physical memory, depending on the physical address size of the processor. For details, see Memory Limits for Windows Releases.
The following demonstration shows how to enable and use OS Invisible Memory. The computer used in this example has 8GB RAM installed and the OS is 32-bit Windows XP. Use Windows Task Manager to take a look on the information of the physical memory. The total memory visible to OS is 3582MB and the available memory is 2975MB.
However, this maximum memory might be further limited by the operating system not being able to address the full range of physical memory. 32-bit operating systems, such as 32-bit types of Windows 7, Vista, and XP, can address approximately 3.3 GB.
Learn how to fix the maximum amount of RAM Windows 7 64-bit can use. Windows 7 and Maximum Memory. Many users of the 32-bit version of Windows 7 were disappointed that not all of their 4GB of RAM (or more) could actually be used by the operating system.
The main difference between 32-bit and 64-bit operating systems is the way that they manage memory. For example, Windows XP 32-bit is limited to a total of 4 GB maximum of system memory to be allocated by the kernel and applications (this is why systems with 4 GB of RAM do not show the total system memory in Windows.
I have Windows XP (32 bit OS) on a Dell GX270. I am planning to upgrade to 4 GB of RAM memory. My question is: will I have full use of all the memory if I make the upgrade?
Physical memory: A 32-bit system generally cannot physically address more than 4GB of RAM (2 32). Systems, however, have adopted extensions that allow a 32-bit processor to physically access more than 4GB of RAM. This is generally implemented via page table hacks.