4 GB of memory

  • Thread starter Thread starter Anders Bengtsson
  • Start date Start date
Well, in a little more detail then:
From address 0xFEC00000 and above there is approximately 20MB set aside
for Motherboard Resources (APIC), and Flash memory controllers.

Below that you have the so called PCI memory range. It contains:
Memory Mapped I/O, PCI/PCI-Express Configuration Space, Additional PCI
Device Memory, chipset resources, Direct Media Interface (DMI) and ICH
ranges.
The size of this area can vary depending on how many hardware devices
are in the system, but usually it is approximately 750MB.

It is important to note that these addresses are used regardless of the
amount of memory installed. The system resources do not actually use
memory, just the addresses. Once the addresses are used for hardware
resources, they are no longer available for memory. Memory that cannot
be addressed will go unused.

Systems with 3.0GB or less are not affected simply because the installed
memory doesn't use these upper addresses. Note that system resources use
the highest addresses and fill down from the top. Any remaining
addresses may be allocated to memory.

Immediately below the PCI memory range is the DRAM range, and this is
what is what can be addressed by the CPU and operating system. A little
chunk of that is the famous 640kb for DOS compatibility. I believe the
memory for video aperture is also taken here in the DRAM range, although
I am unsure.

So all in all, I believe there is not much you can adjust in the BIOS to
make it give back the address space. It would not be dramatic amounts
anyway. However, the amount of RAM available will certainly vary from PC
to PC because of the different hardware configurations, BIOS
technologies and chipsets.

Dell btw put up a support article about it:
http://support.dell.com/support/top...1982C2A2A4B7EAEDB0B57ADD0422B&c=us&l=en&s=gen

Regards,
Frantz Dhin
 
Thank you very much for the explanation and the Dell reference.
Much appreciated.
But, how then does Vista x64 report 4+GB of RAM, and I have added the /PAE switch to the boot.ini of
XP PRO and checked the PAE box in VistaBootPro and XP Pro and Vista x86 still only report 3+GB?

DCR


| Well, in a little more detail then:
| From address 0xFEC00000 and above there is approximately 20MB set aside
| for Motherboard Resources (APIC), and Flash memory controllers.
|
| Below that you have the so called PCI memory range. It contains:
| Memory Mapped I/O, PCI/PCI-Express Configuration Space, Additional PCI
| Device Memory, chipset resources, Direct Media Interface (DMI) and ICH
| ranges.
| The size of this area can vary depending on how many hardware devices
| are in the system, but usually it is approximately 750MB.
|
| It is important to note that these addresses are used regardless of the
| amount of memory installed. The system resources do not actually use
| memory, just the addresses. Once the addresses are used for hardware
| resources, they are no longer available for memory. Memory that cannot
| be addressed will go unused.
|
| Systems with 3.0GB or less are not affected simply because the installed
| memory doesn't use these upper addresses. Note that system resources use
| the highest addresses and fill down from the top. Any remaining
| addresses may be allocated to memory.
|
| Immediately below the PCI memory range is the DRAM range, and this is
| what is what can be addressed by the CPU and operating system. A little
| chunk of that is the famous 640kb for DOS compatibility. I believe the
| memory for video aperture is also taken here in the DRAM range, although
| I am unsure.
|
| So all in all, I believe there is not much you can adjust in the BIOS to
| make it give back the address space. It would not be dramatic amounts
| anyway. However, the amount of RAM available will certainly vary from PC
| to PC because of the different hardware configurations, BIOS
| technologies and chipsets.
|
| Dell btw put up a support article about it:
|
http://support.dell.com/support/top...1982C2A2A4B7EAEDB0B57ADD0422B&c=us&l=en&s=gen
|
| Regards,
| Frantz Dhin
|
| DCR wrote:
| > What BIOS settings?
| >
| > | > | 3071 is not set in stone. It depends on the BIOS settings.
| > |
| > | | > | > Yes, I believe this is a limitation of all 32-bit OSs (2 to the 32nd
| > | > power)
| > | > I get 3071 with Vista x86 and 4000+ with Vista x64
| > | >
| > |
| >
| >
 
32bit Vista RC2 only sees 3 of 4GB memory installed on my Intel D975XBX
mainboard. Vista RC2 x64 sees all 4GB, so this seems not to be a mainboard
problem.
See Thread "Vista RC2 x86 PAE not working. Only sees 3 of 4GB memory" in
microsoft.public.windows.vista.installation_setup.

I opened a service request with Microsoft (SRZ061127002189) to get a
definitive answer.

Here a summary of their answer:
32bit Vista does by design not(!) use the full 4GB of physically installed
RAM.
Technically it could use 4GB (by using PAE to access the memory remapped by
the mainboard above the 4GB address boundary). By a marketing design
decision all Windows Vista 32bit editions are limited to 4GB address space.
Vista Starter ist limited to 1GB. "This is based on marketing decisions and
cannot be cheated with the PAE-Kernel."

I find it hard to believe that someone made such a marketing decision: I can
understand that MS limits physical memory of some Vista edtitions to 4GB. I
do not understand a design decision to not fully use this memory even though
it is technically possible. I assume there are technical or security issues
involved - but this is just my feeling and not based on facts.

Some background links:

Intel® Chipset 4 GB SystemMemory Support
http://www.polywell.com/us/support/faq/4GB_Rev1.pdf

Memory Limits for Windows Releases
http://msdn.microsoft.com/library/d...en-us/memory/base/memory_limits_for_windows_r
eleases.asp

Information regarding PAE-Kernel:
http://msdn2.microsoft.com/en-us/library/ms791485.aspx
http://www.microsoft.com/whdc/system/platform/server/PAE/PAEdrv.mspx
 
Dont quote me on this... I just recently discovered this last night... as I was somewhat unsettled by the fact that I just purchased a 32-bit WIN XP Pro OEM version with no refund or exchange policy. The process is Called GT4. Something to do with the boot sequence and another command line to allocate how much memory you want to go where. Although I do not know much about this... but it seems to me this is mostly only helpful to server OS. Like windows 2003 server. I could be wrong, although I have only done slight research on this. Although I have heard that 64-bit version OS have compatablity problems with drivers, Plugins, etc. Anyways I barely know anything about this, and im a gamer... So im assuming this will affect me. Oh, well there goes 140$ down the drain. Wish I would of knew about this BEFORE I bought... what i thought was an upgrade OS from HOME XP. LOL. I just recently got back into the swing of the technology age. Seems like things have really picked up in only ONE year since I was last in it. Oh well, it is unfortunate to be uniformed. I guess thats what I get for being so hasty in buying my new OS. Very Dissapointing. :-(

EggHeadCafe.com - .NET Developer Portal of Choice
http://www.eggheadcafe.com
 
That may be a BIOS issue (as in hope for an update in the near future),
especially on a recently released mobo. If everything is right you will
see 4GB when running a 64bit OS on a system with 4GB installed.
 
I'm in the same boat as hardoc. I was initially running Vista RC1 (32-bit)
and both my bios and Windows only recognized 3.2GB/4GB on an Asus P5AD2-E
Premium motherboard. I was instructed to get the 64-bit Vista when it came
out, which I've done...Ultimate x64. I'm also running a P4 670 (64-bit
processor). I still only show 3.2GB in both my BIOS and Windows. Asus tried
to say I had bad memory but at boot-up it shows "Dual Channel Interleaved"
just as it should. The memory manufacturer (PQI) had me test each DIMM and
they all came out at the 1024MB they're supposed to. I'm a little upset at
Asus for false advertising. The motherboard and BIOS have got to be to
blame. I can get 3072MB out of 3 DIMMS. Basically I paid $100 for about
130MB/1GB. If I'd known that I'd probably just run 32-bit Windows. Anyone
know anything else I can try?
 
I'm in the same boat as hardoc. I was initially running Vista RC1 (32-bit)
and both my bios and Windows only recognized 3.2GB/4GB on an Asus P5AD2-E
Premium motherboard. I was instructed to get the 64-bit Vista when it came
out, which I've done...Ultimate x64. I'm also running a P4 670 (64-bit
processor). I still only show 3.2GB in both my BIOS and Windows. Asus tried
to say I had bad memory but at boot-up it shows "Dual Channel Interleaved"
just as it should. The memory manufacturer (PQI) had me test each DIMM and
they all came out at the 1024MB they're supposed to. I'm a little upset at
Asus for false advertising. The motherboard and BIOS have got to be to
blame. I can get 3072MB out of 3 DIMMS. Basically I paid $100 for about
130MB/1GB. If I'd known that I'd probably just run 32-bit Windows. Anyone
know anything else I can try? Perhaps a Windows instruction?
 
See my answer in your earlier post regarding this problem.

--


Regards,

Richard Urban
Microsoft MVP Windows Shell/User
(For email, remove the obvious from my address)

Quote from George Ankner:
If you knew as much as you think you know,
You would realize that you don't know what you thought you knew!
 
I am not an expert ( but I read many posts & then tried this )
& the issues was fixed 1st try... !! : ' )
enter Bios
Advance chipset features
memory hole for PCI MMIO
enable feature!
this feature is to remap to address above 4G of ram
save settings & exist
its all there now! from 3070 to 4094!
 
Unfortunately, not all BIOS have that option.

--
Jane, not plain ;) 64 bit enabled :-)
Batteries not included. Braincell on vacation ;-)
studio said:
I am not an expert ( but I read many posts & then tried this )
& the issues was fixed 1st try... !! : ' )
enter Bios
Advance chipset features
memory hole for PCI MMIO
enable feature!
this feature is to remap to address above 4G of ram
save settings & exist
its all there now! from 3070 to 4094!

Anders Bengtsson said:
Hi

Iam running Vista Ultimate 32-bit.
I have installed 4x1GB RAM that I can see in my BIOS
But in Vista I see only 3071 MB of memory (RAM).

How can I make Vista see all my RAM?

Thanks

--

Regards
Anders Bengtsson [MCSE, MCSA, MCP, CNA] | anders AT contoso.se | Website
and
blog: http://www.contoso.se
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