4 Gig or ram- Only showing 3 gig
 

Hello,
Just read the longest post on this issue with no result so let try
again.
If i have 4 gig, only 3 shows, 750mb is reservered for the system.
Doesn't that seem a little stupid? If i have 3 gig of ram, 3 gig
shows in vista, here it has not needed to reserve 750mb. So why does
the first scenario need 750 for the system, and the second does not?
This would mean that the second does not have any ram for its system,
same devices and os. I would have thought that both situations would
result in having 750 stripped for the system. My old box, XP 256 mb
ram all that was avaliable and did not need dedicated system ram.
Does anyone have a straight answer for this? Yes i could run 64 bit
os, but at the moment i want to get 4 gig running in my 32 bit
environment.

I tried the following switches with no change.
1. Reboot Vista to safe mode with command line
2. Run the command : bcdedit /set PAE ForceEnable
3. Run bcdedit again to verify the switch is added
4. Reboot the system and check whether the problem is fixed

This is from the original post:

http://groups.google.com.au/group/mi...dbc2867738d289

"LOL, I was scratching my head over that one too. By definition, a 32-
bit CPU
can directly address up to 4GB of memory. But apparently nearly 1GB of
that
is reserved for devices. So the most you can possibly see is 3.12GB in
a
32-bit system. The way I read it, there is no way around it, no "fix"
if
you're using a 32-bit version of Vista.

To see any more than 3.12 GB you have to be using a 64-bit version of
Vista
plus meet all those other requirements (64-bit CPU instruction set,
chipset
with 8GB address space, BIOS that supports memory remapping). That's
the way
I read it anyway.

I think the DEP/ PAE thing is a whole different (but related) issue. "

4 Gig or ram- Only showing 3 gig
 

Depending on what devices are mapping themselves in
you will get access to about 3.12 Gig or less.

http://support.microsoft.com/kb/929605/en-us

http://support.microsoft.com/kb/294418/en-us

wrote in message
ups.com...
Hello,
Just read the longest post on this issue with no result so let try
again.
If i have 4 gig, only 3 shows, 750mb is reservered for the system.
Doesn't that seem a little stupid? If i have 3 gig of ram, 3 gig
shows in vista, here it has not needed to reserve 750mb. So why does
the first scenario need 750 for the system, and the second does not?
This would mean that the second does not have any ram for its system,
same devices and os. I would have thought that both situations would
result in having 750 stripped for the system. My old box, XP 256 mb
ram all that was avaliable and did not need dedicated system ram.
Does anyone have a straight answer for this? Yes i could run 64 bit
os, but at the moment i want to get 4 gig running in my 32 bit
environment.

I tried the following switches with no change.
1. Reboot Vista to safe mode with command line
2. Run the command : bcdedit /set PAE ForceEnable
3. Run bcdedit again to verify the switch is added
4. Reboot the system and check whether the problem is fixed

This is from the original post:

http://groups.google.com.au/group/mi...dbc2867738d289

"LOL, I was scratching my head over that one too. By definition, a 32-
bit CPU
can directly address up to 4GB of memory. But apparently nearly 1GB of
that
is reserved for devices. So the most you can possibly see is 3.12GB in
a
32-bit system. The way I read it, there is no way around it, no "fix"
if
you're using a 32-bit version of Vista.

To see any more than 3.12 GB you have to be using a 64-bit version of
Vista
plus meet all those other requirements (64-bit CPU instruction set,
chipset
with 8GB address space, BIOS that supports memory remapping). That's
the way
I read it anyway.

I think the DEP/ PAE thing is a whole different (but related) issue. "

4 Gig or ram- Only showing 3 gig
 

also, my first reply on this:
someone posted that if you use PAE you could get the full 4 gig
showing, but it wont make any difference as the system will still need
to use 750mb for itself.
then why would a xp machine with 128 mb not fall over it would show
128mb, but need a fair wack for the system??
Sounds like to different outcomes?? which brings me to the original
point. The system cant hide the ram and use it for itself. XP and
Vista are the system and they use the ram that it can see and no more
"extra hidden ram".
how could a system address ram that it has not detected??

4 Gig or ram- Only showing 3 gig
 

Try an experiment.
Turn off all virtual memory, page files, set it all to zero.
Reboot and see if you notice any performance difference in your 4 gb
machine.

4 Gig or ram- Only showing 3 gig
 

Wouldn't make any difference, the memory *addresses* are reserved by the
system.

--
Best of Luck,

Rick Rogers, aka "Nutcase" - Microsoft MVP
http://mvp.support.microsoft.com/
Windows help - www.rickrogers.org
My thoughts http://rick-mvp.blogspot.com

"babaloo" wrote in message
. net...
Try an experiment.
Turn off all virtual memory, page files, set it all to zero.
Reboot and see if you notice any performance difference in your 4 gb
machine.

4 Gig or ram- Only showing 3 gig
 

Hi,

You aren't fully reading the explanations. It is the addresses that are
reserved for the system, and this is regardless of how much ram is
installed. In XP you didn't see it because the amount of ram installed was
nowhere near the 4GB of addressing space of this 32-bit OS. The /PAE switch
allows for more addressing space, so then you can see it.

--
Best of Luck,

Rick Rogers, aka "Nutcase" - Microsoft MVP
http://mvp.support.microsoft.com/
Windows help - www.rickrogers.org
My thoughts http://rick-mvp.blogspot.com

wrote in message
oups.com...
also, my first reply on this:
someone posted that if you use PAE you could get the full 4 gig
showing, but it wont make any difference as the system will still need
to use 750mb for itself.
then why would a xp machine with 128 mb not fall over it would show
128mb, but need a fair wack for the system??
Sounds like to different outcomes?? which brings me to the original
point. The system cant hide the ram and use it for itself. XP and
Vista are the system and they use the ram that it can see and no more
"extra hidden ram".
how could a system address ram that it has not detected??

4 Gig or ram- Only showing 3 gig
 

On Aug 6, 10:02 am, "Rick Rogers" wrote:
Hi,

You aren't fully reading the explanations. It is the addresses that are
reserved for the system, and this is regardless of how much ram is
installed. In XP you didn't see it because the amount of ram installed was
nowhere near the 4GB of addressing space of this 32-bit OS. The /PAE switch
allows for more addressing space, so then you can see it.

Rick just to clarify, "so then you can see it". Even if i can see it
with a /PAE switch = 4gig, the machine will only ever use say 3 gig
because the other part is reservered for the system addresses. So the
max ram that can be used comes down to how many addresses it needs to
allocate for the system eg 750mb leaving the remaining addresses out
of 4096mb to be allocated to ram.

Long answer and short answer, is machines are now made for 64 bit ram
sizes, and 64 bit cpu's and dual cores, turn your Windows cd into
coasters and go and buy 64 bit OS's now!!

4 Gig or ram- Only showing 3 gig
 

wrote in message
ups.com...
If i have 4 gig, only 3 shows, 750mb is reservered for the system.
Doesn't that seem a little stupid? If i have 3 gig of ram, 3 gig
shows in vista, here it has not needed to reserve 750mb.

Yest it has reserved 750MB, itt's just that the 750MB is above the 3GB
so you don't see it. When you have 4GB RAM, the 750MB has to be
taken out of the total.

So why does
the first scenario need 750 for the system, and the second does not?

Here's the diagram again:

System total:
|-------------------------4GB-------------------------------|

With 4GB:
|---------------3GB RAM-----------------|----System------|

With 3GB:
|---------------3GB RAM-----------------|----System------|

With 2GB:
|--------2GB RAM------------|--Unused--|----System------|

With 3GB or less, you won't see any difference between installed
RAM and amount available to Windows.

Tom Lake

4 Gig or ram- Only showing 3 gig
 

On Sun, 5 Aug 2007 20:02:16 -0400, "Rick Rogers" wrote:

You aren't fully reading the explanations. It is the addresses that are
reserved for the system, and this is regardless of how much ram is
installed. In XP you didn't see it because the amount of ram installed was
nowhere near the 4GB of addressing space of this 32-bit OS. The /PAE switch
allows for more addressing space, so then you can see it.

This is really funny, like deja vu all over again.

Remember when IBM put all the ROMs at 640k because "no-one would ever
need that much RAM"?

Still, the system mappings have to do somewhere, I guess. Do they
fill the top part of the map, or is it a matter of 5M worth of stull
scattered from 3.12G upwards, breaking contiguous addressability?

Does addressability still need to be contiguous, in the post-286 age?



------------ ----- ---- --- -- - - - -
The most accurate diagnostic instrument
in medicine is the Retrospectoscope
------------ ----- ---- --- -- - - - -

4 Gig or ram- Only showing 3 gig
 

Hi Chris,

Remember when IBM put all the ROMs at 640k because "no-one would ever
need that much RAM"?

Indeed, still talk about that with the old pc buffs.

Still, the system mappings have to do somewhere, I guess. Do they
fill the top part of the map, or is it a matter of 5M worth of stull
scattered from 3.12G upwards, breaking contiguous addressability?

I honestly don't know on this one. I can't see where that much system
address space is required, but then again you never know. I think it's more
along the lines of an arbitrary point chosen as the cut off line, and
anything above it is marked as reserved, used or not.

Does addressability still need to be contiguous, in the post-286 age?

I don't believe so, but again I don't know for sure.

--
Best of Luck,

Rick Rogers, aka "Nutcase" - Microsoft MVP
http://mvp.support.microsoft.com/
Windows help - www.rickrogers.org
My thoughts http://rick-mvp.blogspot.com

"cquirke (MVP Windows shell/user)" wrote in
message ...
On Sun, 5 Aug 2007 20:02:16 -0400, "Rick Rogers" wrote:

You aren't fully reading the explanations. It is the addresses that are
reserved for the system, and this is regardless of how much ram is
installed. In XP you didn't see it because the amount of ram installed was
nowhere near the 4GB of addressing space of this 32-bit OS. The /PAE
switch
allows for more addressing space, so then you can see it.

This is really funny, like deja vu all over again.




------------ ----- ---- --- -- - - - -
The most accurate diagnostic instrument
in medicine is the Retrospectoscope
------------ ----- ---- --- -- - - - -