128gb RAM on Windows 7 32bit

A quick note for those who haven't heard of this before, I hadn't until yesterday..

Yup more than 4GB RAM on 32 bit Windows


I found an article which explains that the restriction is not due to it being 32 bit but because of licensing and that all the code to address more RAM is already in the OS. After all how did Windows 2000 address upto 32GB RAM and that's 32bit?

Anyway you have to use a modified kernal and change some of the BCEDIT settings that allow you to boot the patched kernal with test mode enabled.

You can read up everything here;


Removing the 4 GB license limit in Vista/Win7 32 bit - Ars Technica OpenForum <--- Auto patcher
Windows 7 Starter with (up to) 128GB RAM - feilipu's posterous <--- Manual patch instructions
Licensed Memory in 32-Bit Windows Vista <--- original research


I have run this on my Windows 7 starter 32bit netbook and it worked fine, however I did the bcedit things manually as I'd already started because I hadn't yet found the auto patcher.


I guess it begs the question, is this now faster than 64bit as that can carry a processing overhead?

 

Since when? This is only possibly an issue when emulating 32bit applications and I've never seen any benchmark show any difference at all. When running native 64bit applications it can be considerably faster than 32bit.

Pretty cool though, thanks.

 

total waste of time,

if you have more than 4 GB, install 64 bit Windows and it's done

there is no reason not to use 64 bit anymore as most programs work on 64 bit Windows

 

While the 64bit version does use a small amount more RAM, somewhere in the 5% range, if you have that much RAM you should be using 64bit. The RAM available for each process is still limited to 32bit.

 

The 32-bit 'hack' you are referring to is what we call PAE.

I'll quote the important bit here:

In the end MS set it up so that you had to have a PAE aware OS, PAE aware software, and PAE aware drivers to reliably use more than 4GB of RAM. The additional cost for testing and QA put these features squarely in the enterprise (business) domain. It was a nice idea but with modern 64bit processors the feature is simply not needed anymore.

I simply do not understand why people want to make it more difficult on themselves with untested and untrustworthy PAE hacks. Just install a 64-bit version of Windows and be done with it.

 

Yep I have starter edition on my netbook which is why I looked into this in the first place for my netbook. Also dont forget that you might be wanting to upgrade an older machine that is 32 bit only.

I also have a 32bit joojoo windows tablet that would allow it to use all of the 4gb of ram and not just ~3.2GB

Also if you buy a computer and it comes with 32bit windows pre-installed and you dont have a windows install disc do you actually have the ability to even change to 64bit without having to buy a new copy of windows as you only get the manufacturers restore discs?

 

You can download a Windows 7 x64 ISO from the links provided in these forum (perfectly legally), and can activate it with the key on the bottom of your laptop, even if it originally only came with 32-bit. I have done this on my old Toshiba laptop.

There is no reason to be using this "hack" when you can get a 64-bit ISO for free. Anything that's old enough to be incompatible with x64 is probably incompatible with PAE as well.

 

How many netbooks and tablets that come with 32 bit W7 can even hold more than 4 GB?

 

Exactly. Many netbooks come with a single RAM slot. Plus many netbook CPU's like variations of the Atom can't manage more than 4GB anyhow. Heck earlier Atom CPU's didn't even have 64-bit instructions. PAE was a workaround in a time when 4GB RAM was very expensive and really only required for memory hungry apps running on systems that were designed for such tasks. Not notebooks. If you need more than the allocated 3.2GB+ from a 4GB stick then you need more than a netbook.

Windows Starter was the dumbest idea ever by Microsoft (well aside from Bob). It was good concept, something designed specifically for netbooks, but in the end they opened up a lot of features that were initially designed to be restrictive (like limiting number of simultaneously opened apps). Thank goodness Windows 8 will be 64-bit only (I believe).

 

lol, discussing 4GB or more on a 32-bit OS is IMO probably more futile than discussing the dreaded "pagefile"

I think your 128GB is assuming using 2 CPU's with 36-bit addressing. 32-bit PAE can allow addressing much higher than that, but the limiting factor for the OS will likely be PTE storage.

Speed difference for most will not be noticeable but to run 32-bit at it's fastest would be to not use PAE. IMHO unless your trying to break some benchmark world record it's not going to make much difference.

There are still a lot of processors out there that are 32-bit where installing a 64-bit OS isn't an option. Especially Atom processors, some of these processors only went into production Q3 2010. The HW of those systems employing these CPU's might not be able to address higher than 4GB so in that case it would not help. But of course some people may have reasons for running a 32-bit OS other than due to hardware. Making the full 4GB available is probably a gray area, making use of more than 4GB is against your licensing. MS have capped 32-bit client OS's to 4GB just as they capped 64-bit home basic to 8GB. If you want to use more than 4GB then IMO either use a non-MS product or/and a 64-bit OS.

The software does not have to be PAE aware and the "hack" does not change PAE but changes memory management.

FWIW I did my own testing quite some time ago with 32-bit and full use of 4GB and never had an issue with Vista, VistSP1, VistaSP2, W7 or W7SP1 using a multitude of different hardware and drivers.

How did you come to that conclusion? IIRC PAE became available on processors in 1995.


64-bit does offer a lot of advantages over 32-bit but you do need 64-bit applications to make use of them. The only advantage I can think of for 32-bit app's on a 64-bit OS is if they are large address aware in which case they can make use of almost 4GB of memory although still limited to a maximum contiguity of address space of ~2GB.

It is also possible to use more than 4GB for a 32-bit application using AWE but without client OS support for more than 4GB of memory your not likely to find it being used except in the server OS's.