What is the max ram for Vista 32 bit?

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Incorrect. A 32 bit OS cannot go beyond 4GB of addressable memory, ever. And it has nothing to do with the developers coding support for more than 4 in the OS.

Why? A 32-bit register means that 2^32 addresses, or 4 gigabytes worth, can be referenced. This is a hard, mathematical limitation. This 4GB includes system memory, video RAM, and any onboard memory - anything that uses an address. This is why users see less than 4 if that's what they installed. What happens is the OS assigns addresses in order of importance: whatever's on the Mobo, then Video, and then the installed DIMMS. What you see displayed as usable is the value of your physical RAM less Video and onboard.

You may be able to put more physical RAM on the Mobo...

dengamle

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Some people only sees 2GB (exactly), but this is often due to memory remapping being enabled in bios. This should be disabled when using 32-bit vista/xp

"any 32bit OS" might be too much. If supported, they can go well above 4GB
 
Incorrect. A 32 bit OS cannot go beyond 4GB of addressable memory, ever. And it has nothing to do with the developers coding support for more than 4 in the OS.

Why? A 32-bit register means that 2^32 addresses, or 4 gigabytes worth, can be referenced. This is a hard, mathematical limitation. This 4GB includes system memory, video RAM, and any onboard memory - anything that uses an address. This is why users see less than 4 if that's what they installed. What happens is the OS assigns addresses in order of importance: whatever's on the Mobo, then Video, and then the installed DIMMS. What you see displayed as usable is the value of your physical RAM less Video and onboard.

You may be able to put more physical RAM on the Mobo, but you cannot use it.

To use more than 4GB total addressable memory, you much go to a 64bit OS. That gives 2^64 (17,179,869,184 gigabytes) of addressable space.
 
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dengamle

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The virtual addressing part means that an application is fixed at 4GB address space no matter what. But the physical address space can be bigger, so many processes or an application coded for AWE can take advantage of this
 
You are correct: PAE allows 32-bit OS's (like Windows Server 2003) to access the full 4GB.

However, from a more pragmatic point of view: Microsoft has pretty much abandoned using PAE for the 32-bit versions of Windows XP SP2 and Windows Vista. Why? Because vendors do not code consumer-targeted drivers to take advantage of PAE. So what you get is all kinds of support problems, such as when incorrectly written device drivers attempt Direct Memory Access operations, for example.

Check: http://support.microsoft.com/kb/929605/en-us "To avoid potential driver compatibility issues, the 32-bit versions of Windows Vista limit the total available memory to 3.12 GB"

Yes, PAE enables 4GB and greater. But Microsoft have basically decided they have (or are getting blamed for...) more than enough issues with badly written drivers causing OS issues. Therefore they don't support PAE in 32 bit OSs, so it's a non-issue in the context of this thread. In a MSFT~dominated world, the answer is still "No, you have to go to XP/Vista 64 to fully utilize 4GB+ of RAM".


For the OP: RAM is cheap, and you should be able to get around 3GB of usable RAM on XP/Vista unless you are running Crossfire/SLI and therefore have a huge amount of Video Ram that needs to be addressed.
 

dengamle

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yes, one of their reasons for limiting the address space in xp and vista is bad drivers. This might also be why people sometimes gets confused about the pae switch, the pae kernel is there and can be loaded, but for other reasons than addressing more than 4GB
 

dmroeder

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noted...
 

n2deepwnv

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Im Sorry to say.....Ummmm no, Actually Im Happy To Say, That is totally incorrect and I can prove it! I am Running Windows Vista. A 32 bit os at 8 gigs of ram! Promise not a 64 bit. Not only does it show, it uses it too! I know That sounds like Im lying But Maybe I Have A Freak Of Nature Computer.


 



HOW have you proved it?

Prove it with a screenshot please.

I don't mean to be mean but you would be the only one I have ever hear of. Vista will REPORT that you have 4 or more gig of RAM installed and your BIOS will see it, this often leads people to believe their 32 bit Vista is USING 4 or more gig of RAM but the OS will not be using it on Vista 32 unless you have hacked the OS in some way that no one else has ever publicly demonstrated.
 



I must have missed it.

BTW Why would you say this and not provide a link?

Also this poster makes no claim to have done anything special to his computer.

If you are talking about PAE (BCDEdit /set PAE forceenable) then this is an urban myth as far as I can tell. You have a few people saying it works but the vast majority of people who tried it report it did not work.
 


OK. I'd buy that if I could find some definitive info on it but Google shows almost nothing except the same old PAE stuff. Extraordinary claims require extraordinary proof.
 

somenewb

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im using a dv6000 laptop it had 1g of ram, i updated my bios(wasnt working when i didnt) just before upgrading to 4g(2x2g) kingston. the computer only recognised 3g. i decided to update windows using Windows Update. i installed packages 1 and 2.(took like 3hrs) then when i opened 'my computer' it listed Memory: 4.00 GB, im not sure but i think the packages that did it.
 

Beetlebox

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All you have probably done is changed the way Vista reports RAM. If you check the task manager it will probably only show 3GB still.


mikerev007 is right, nothing extraordinary about it. It has been demonstrated sometime ago by

1. Using parts of 2008 server version (too lazy to find the original link)
http://www.midmee.com/xe/?mid=freetalk&document_srl=82&sort_index=readed_count&order_type=desc

2. Patching the kernel
http://www.geoffchappell.com/notes/windows/license/memory.htm

Not being able to run all 4GB or more of RAM on Vista is really mind over matter. Not enough people mind that the 32-bit doesn't support 4GB or more so it doesn't matter. :lol:

To the OP, expect less than 4GB of usable RAM with Vista 32-bit. :kaola:
 

nintool3369

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Whoever gets into this thread and claims that they are using more than 4GB of RAM in any Microsoft-based client OS like Vista 32bit or XP 32bit, etc, etc...they are absolutely crazy. This is NOT POSSIBLE, other than the kernel being hacked and using the /PAE ... switch on your boot.ini file. PAE is used to address anything beyond what the OS cannot use, but you still aren't really using 4GB. Even if you install 16GB you won't use it. Period.

Good luck to the idiots that purchase all that ram, and run a 32bit OS. Why don't you just try to run a 16bit version of DOS or something on your machine and claim that you can go beyond 64MB of ram lol....although with hacks anything could be possible. Just know your limits in simple math really...

Or just go shell out for that 64bit OS. Don't waste the hardware if your gonna go buy or build something that has a 64bit capable CPU and a boat load of RAM in it, might as well build an Auto-CAD machine...ha!
 
Its clear that some people have no clue how Windows and programs actually access RAM.

http://www.tomshardware.com/forum/258528-30-explained
http://en.wikipedia.org/wiki/Physical_Address_Extension

In computing, Physical Address Extension (PAE) is a feature of some x86 and x86-64 processors that enable the use of more than 4 gigabytes[1] of physical memory to be used in 32-bit systems, given appropriate operating system support. PAE is provided by Intel Pentium Pro and above CPUs (including all later Pentium-series processors except the 400 MHz bus versions of the Pentium M), as well as by some compatible processors such as the Athlon and later models from AMD.

The x86 processor hardware is augmented with additional address lines used to select the additional memory, so physical address size is increased from 32 bits to 36 bits. This increases maximum physical memory size from 4 GB to 64 GB. The 32-bit size of the virtual address is not changed, so regular application software continues to use instructions with 32-bit addresses and (in a flat memory model) is limited to 4 gigabytes of virtual address space. The operating system uses page tables to map this 4 GB address space into the 64 GB of RAM, and the map is usually different for each process. In this way, the extra memory is useful even though no single regular application can access it all simultaneously.

All the /PAE switch does is access the 36-bit mode (68,719,476,736 bytes = 64GB) that used to be standard back in the mid-late 80's.
 
PAE is not enabled for client OSs for the purpose of increasing address space. It is only available for DEP. This is intentionally done by Microsoft. 4GB is the total space allowed on the client. No more.

This topic has been beaten to death.



{Edit to provide link to MSFT's KB stating 4GB and 4GB only}

Please note - XP32 (All Versions) can only have 4GB under any circumstances.
http://www.microsoft.com/whdc/system/platform/server/PAE/PAEdrv.mspx
 

mikrev007

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Yes, PAE is crippled in those editions, but the talk was about modifying the kernel to remove that limitation. And the statements about 32bit OSes are mathematically locked at 4GB nomatter what are false.
 
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