Quote: Originally Posted by SamCPP
Quote: Originally Posted by biggles1000
I'm afraid 32 bit windows 7 has a 3.5GB RAM limit no matter what. The limits then vary working your way up the 64 bit version ladder. (the unofficial PAE stuff for Windows 7 is unstable)
Actually, scratch that. Apparently the limit is 4GB for all 32 bit versions but starter :/
32-bit server editions of windows can actually use up to 128GB (Win2k3 x86 Datacenter edition) so technically 32-bit Windows CAN use more than 4GB of memory (as implied by pallesenw
). Memory Limit – Windows Server 2003 | SQL Server Training Pushing the Limits of Windows: Physical Memory - Mark's Blog - Site Home - TechNet Blogs
The reason it is not supported in end-user versions of the 32-bit operating systems is mainly due to drivers
from my understanding. Poor nvidia and creative drivers back in the day.
On consumer versions of Windows, PAE not used for memory. DEP (Data Execution Prevention) and a couple other tricks, yes. But not for memory.
The way it works for Memory is it allows an added table the OS can use to add the “same” address in more than one place. Think of this as adding a "street name" to your "address". 1234567890 on table A is not the same as 1234567890 on table B. The limitation is that this *must* be provided for in your programs and drivers in order to work. If your mailman only looks at the '1234567890' but never looks at the street name, then he can and will sometimes deliver a letter to the wrong place. The same thing is true of PAE - If/when then individual program haven’t been coded to look in multiple tables for the needed memory locations in addition to the numerical addresses, messages can and will often go to the wrong place. In Windows, this is a called a “memory access violation”, and results in a blue screen. Additionally, individual programs under PAE can still only use up to 4 GB. Kernels and drivers can be made aware of PAE, but they can still only use 4 GB ranges at a time.
In short: PAE is not that great. In a server environment the number/version/type of programs and drivers can be tightly controlled, so this works and so this functionality is available on server versions of 32 bit Windows (NT, 2003, 2006, etc). In a consumer environment, this is not true at all.
Bottom line for ‘regular’ users: If you want to use 4 GB of RAM or more, then you should buy 64-bit hardware and use a 64-bit OS.