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Behind the 4GB Memory Limit In 32-Bit Windows
An anonymous reader points us to a very detailed post by Geoff Chappell, first put up early this year, explaining how the 4GB memory limit commonly bandied about for 32-bit Windows (he is writing mainly about Vista) is more of a licensing preference than an architectural limit. The article outlines how Chappell unlocked his system to use all the memory that is present, but cautions that such hackery is ill-advised for several reasons, including legal ones. "If you want [to be able to use more than 4GB in Vista] without contrivance, then pester Microsoft for an upgrade of the license data or at least for a credible, detailed reasoning of its policy for licensing your use of your computer's memory. ... [C]onsider Windows Server 2008. For the loader and kernel in Windows Vista SP1 (and, by the way, for the overwhelming majority of all executables), the corresponding executable in Windows Server 2008 is exactly the same, byte for byte. Yet Microsoft sells 32-bit Windows Server 2008 for use with as much as 64GB of memory. Does Microsoft really mean to say that when it re-badges these same executables as Windows Vista SP1, they suddenly acquire an architectural limit of 4GB? Or is it that a driver for Windows Server 2008 is safe for using with memory above 4GB as long as you don't let it interact with the identical executables from Windows Vista SP1?"
I skimmed the article.
What it boils down to is : it's possible for 32-bit windows to use more than 4 gigs of memory. Microsoft doesn't allow this for the consumer licensed versions of Windows. While the article makes various allegations that Microsoft is doing this to be bad, the author found out that many device drivers intended for 32 bit windows will break if PAE is enabled. In addition, PAE is an ugly hack, and it still won't let a single thread access more than 3 gigs of RAM. These days, single applications like games and video editing software can easily use more than 3 gigs of RAM.
Long story short : Get, and use 64-bit Windows for Windows machines with a lot of RAM. Since 64-bit XP is poorly supported, and Vista is dog-shit, then that means you should be using 64-bit Windows 7.
And in other news, it costs precisely the same to press a copy of Vista Home Crippled versus Vista L337 OMG, and yet Microsoft charges differently based on which bits are enabled on the particular copy that HP installed on your laptop. This called "market segmentation". If you think a proprietary software company's going to give the cheap version all the same features as the expensive one, just because it wouldn't directly cost them more to do so, then you are hopelessly naive.
Dewey, what part of this looks like authorities should be involved?
It would be pretty hard to get worked up about what you lose from the memory mapped regions(except on aesthetic grounds), except that your video RAM is one of those regions. All the weird legacy stuff below 16 megabytes is very nearly a rounding error; but with cheap, basic graphics cards packing 512megs(and high end cards pushing 1.5gigs, and possibly more than one card per system) you can exhaust a fair slice of the first 4GB that way.
Why is /. greenlighting yet another article just for the sake of MS-bashing? Other posters have already pointed out the remaining process memory limits and consumer driver issues that make this a non-starter technically. Not to mention that there's not much (any?) consumer-level 32-bit hardware that has BIOS/Northbridge support for more than 4GB of RAM. Since the 64-bit versions don't cost any more, who cares?
But this guy is saying that Microsoft is doing something "illegal" because he was able to hack his system and enable PAE, even though MS charges extra for that in their server OSes. Is it "illegal" for Ford to sell me a car that's computer governed to 105 MPH even though the engine can get it up over 130? Can I complain to the FTC if I chip the car to remove the limit and then destroy the transmission?
No sig, sorry.
there are no real technical reasons
Well, other than for crappy software that assumes that an address is 32 bits...
Or hardware that doesn't have drivers for 64-bit systems...
So, yes, no technical reasons at all...
That is all.
Not only that but I have to call FUD, as there is a REASON why 32bit XP and Vista don't support more than 3.25 and it AIN'T about licensing. You want to know why? One word-drivers. I have found that there are plenty of seriously flaky drivers that act buggy as hell if PAE is used, and that is with the standard 3.25Gb limit. Capture cards, some of the older Sata and IDE cards, and those are just the ones off the top of my head that I have run into personally.
So while there are those that want to scream about MSFT and look for any reason to have a shitfit, considering the 64bit and 32bit OS editions are the same price it makes no sense. More likely MSFT tested extending PAE like they allow with 2K3 and found that non server (read Cheap Chinese Crap) drivers get uberflaky and fuck up with large amounts of RAM enabled. This of course would lead to a HUGE spike in the "Why don't my shit work? Fix it!" calls to MSFT, and they decided it just wasn't worth the hassle. At least with X64 they can say "Hey it ain't OUR fault, as we didn't build the device. Contact the manufacturer for a driver" whereas with 32bit folks would go "I GOT a &%&^ driver! Your OS don't work!" thus raising support costs.
So in a way it IS a business decision, but it ain't got to do with licensing. It has to do with the millions of 32bit drivers out there, a probably not insignificant amount of which don't play nice with PAE over 4Gb.
ACs don't waste your time replying, your posts are never seen by me.