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How can I enable PAE on Windows 7 (32-bit) to support more than 3.5 GB of RAM?

I have a laptop which has 2GB DDR III RAM, 520MX 1GB Graphic, and Intel Core i3-2310M CPU @ 2.10GHz.

I use W7 32bit (I don't want to use 64bit W7), and I don't have enough RAM for some applications something like I am using Virtual Machines, MS Office 2010, PS5, CorelDraw X5, Nero 11, MS Visual Studio 2010, and many others. So I added two 4GB RAM for the machine. But I found that only 2.66GB usable instead of 8.00GB. Is there anything else I need to change in my system?

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marked as duplicate by nhinkle Mar 6 '12 at 5:21

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

You shouldnt mix RAM like that. Also requires 64-bit windows – Simon Sheehan Mar 6 '12 at 3:46
> You shouldnt mix RAM like that. Also requires 64-bit windows What mixing? Both replacement sticks are 4GB, presumably from a kit. – Synetech Mar 6 '12 at 4:34
Sorry, but the answer is basically "too bad". The x86 architecture is inherently restricted on a physical level to ~3GB of RAM. You can kind of use PAE as a workaround, see link above. But why don't you want to use Windows x64? Perhaps there's a deeper problem we can help you solve? – nhinkle Mar 6 '12 at 5:20
Disable memory remapping in the BIOS (if it allows it). This might get you an extra 800MB or so. – David Schwartz Mar 6 '12 at 5:22
Both replacement sticks are 4GB. Anyway, Thank you all, I finally installed W7 x64. – Wadi Naw Mar 6 '12 at 16:22

1 Answer 1

Your system has 1 GiB of graphics memory, and only 32 bits with which to address memory.

That means you have 232 - 230 = 3 GiB of address space left.

Subtracting away other device ranges and the amount of RAM that the OS needs, that leaves you with the ~2.6 GiB you mentioned.

Of course, applications probably won't be able to even use that much, because 1 GiB of address space is reserved for the kernel.

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Then, tell me how to do? Upgrade W7 64bits? – Wadi Naw Mar 6 '12 at 4:32
Here's a list of Microsoft operating systems and their maximum memory sizes. – Eroen Mar 6 '12 at 4:37
@WadiNaw: Yeah. – Mehrdad Mar 6 '12 at 4:44
Thanks all. Your suggestions are really helpful! – Wadi Naw Mar 6 '12 at 16:26

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