Re: Physical Address Extension (PAE) does not work on vista as expected.

The point is:
If you don't have more than 4GB of memory, PAE will not change how
memory is reported.

It is supported, but only through BCEDIT:
Support info:
http://msdn.microsoft.com/en-us/library/ms791485.aspx

BCEDIT commands:
http://msdn.microsoft.com/en-us/library/aa906211.aspx
This one will also link you back to the first link and comment I provided
about only having 4 GB memory installed.


"Sarah White" <kuzetsa@xxxxxxxxxxxx> wrote in message
news:ueOknvlyIHA.5620@xxxxxxxxxxxxxxxxxxxxxxx
Err... obviously :-P

Yes, 32bit addressing has a 4GB limit. That's the whole point of PAE. I
suppose I should have asked "what are the steps required for using PAE
to actually remap addressing to the extended areas?"

Based on the behavior I am seeing, I'm inferring that my video card
drivers aren't detecting PAE (and / or realizing my cpu supports 64 bit
instructions) and as a result, the driver's DMA / MMIO (or whatever
technical jargon applies here) is falling back on non-PAE mode and using
addresses inside the 32-bit RAM area.

I'm outright frustrated that when I "upgraded" my 3 year old edition of
Windows XP Pro x64 (2005 edition) to Windows Vista Home (32bit, and SP1
is brand new) that enabling PAE is no more successful than it was in XP.
I could understand if the drivers weren't digitally signed / WHQL
certified, or if the hardware was not capable of 64bit mode, but these
drivers are digitally signed, and the drivers for XP Pro x64 worked
flawlessly.

Any rate, yesterday I invoked the "windows anytime upgrade" feature in
windows, paid a bit of money and such. In the next few weeks I'll be
receiving vista "ultimate"... I'll once again opt-in / elect to join the
"Help Experience Improvement program".

...I already felt it neccessary to submitted a comment about vista's
built-in "help and support" definition of PAE:

--snip--

Physical address expansion (PAE)

A feature that allows x86-based computers to support more than 4
gigabytes (GB) of physical memory. Up to 64 GB of physical memory can be
used as regular 4-kilobyte (KB) pages, and the number of bits that can
be used by the kernel to address physical memory can be expanded from 32
to 36.

--snip--


Mark H wrote:
If you are running a 32-bit version of Windows Vista on a computer that
has
4 GB of memory installed, the amount of RAM available for use could be
less
than what you would expect. For more information about memory usage, see
article Q929605, in the Microsoft Knowledge Base.

http://support.microsoft.com/?kbid&ID=929605


.

Relevant Pages

  • Re: ram ..please help
    ... However I personally don't think there was anything like that decision making involved with PAE. ... A typical consumer box at Best Buy or Comp USA was going out the door with WinME and 128mb of ram with mobos whose memory controllers were limited to 512mb of ram. ... It cost the buyer a couple of hundred bucks to upgrade to 512mb and mobos with three memory slots did not support anything more than 768mb. ... They were addressing a need expressed by enterprise users. ...
    (microsoft.public.windows.vista.hardware_devices)
  • Re: 4GB of RAM tunning in windows xp professional xp sp2 with 32bi
    ... I saw that all is saying "NO" to support of memory more than 4GB in 32Bit OS. ... Support for PAE is provided under Windows 2000 and 32-bit versions ...
    (microsoft.public.windowsxp.general)
  • Re: Cannot activate sbcl
    ... Somehow I've managed to use 16GB and I'm using the 32bit version of Windows XP, and I was able to use all that memory (e.g. ... supports PAE. ... at any one time, but can access RAM above 4GB through AWE, a paging ...
    (comp.lang.lisp)
  • Re: A8N-SLI SE and PAE
    ... He wants to max out the board with 4Gb of RAM so I wanted to make sure it was possible to set PAE on so it dosn't let most of the last 1Gb go to waste. ... I don't know which BIOS it's currently using but we can update it if needed. ... If there's no PAE or memory hole options we can try PAE in the boot.ini but I don't know if thats going to work. ... The following table specifies the limits on physical memory for Windows XP. ...
    (alt.comp.periphs.mainboard.asus)
  • Re: A8N-SLI SE and PAE
    ... He wants to max out the board with 4Gb of RAM so I wanted to make sure it was possible to set PAE on so it dosn't let most of the last 1Gb go to waste. ... I don't know which BIOS it's currently using but we can update it if needed. ... If there's no PAE or memory hole options we can try PAE in the boot.ini but I don't know if thats going to work. ... The following table specifies the limits on physical memory for Windows XP. ...
    (alt.comp.periphs.mainboard.asus)