Total Physical Memory on Task Manager shows wrong value?

This is with Vista SP1 installed. I added 2GB RAM making the total
installed RAM size to be 4GB.
My problem is that although BIOS recognize the RAM size to be 4GB and
the Properties/System shows also 4GB, but both of the System
Information/System Tools and Performance/Task Manager show 2GB.

How can I check to see if 4GB is being made available for the system to
utilize?

32 bit or 64 bit vista?


Post Originated from Vista Support Forums

It is 32 bit Vista.

Jordus wrote:
> 32 bit or 64 bit vista?
>
>
> Post Originated from Vista Support Forums

churin <> wrote:

>This is with Vista SP1 installed. I added 2GB RAM making the total
>installed RAM size to be 4GB.
>My problem is that although BIOS recognize the RAM size to be 4GB and
>the Properties/System shows also 4GB, but both of the System
>Information/System Tools and Performance/Task Manager show 2GB.
>
>How can I check to see if 4GB is being made available for the system to
>utilize?

4GB is *not* available to your system. You have a 4GB address space,
but some of that must be used to access BIOS, video RAM, etc. What's
left over is used to access RAM. See
http://members.cox.net/slatteryt/RAM.html

That said, I'd expect you to see more than 2GB. Do you have multiple
fancy video cards, or something else that might include lots of
onboard RAM?

--
Tim Slattery
MS MVP(Shell/User)

http://members.cox.net/slatteryt

> How can I check to see if 4GB is being made available for the system to
> utilize?
It sounds like the RAM isn't being detected. What does the BIOS show?
Either way, the maximum amount of RAM you will be able to access (without
enabling PAE) is 3.2GB.

(oops. "Reply Group")

> How can I check to see if 4GB is being made available for the system to
> utilize?
It sounds like the RAM isn't being detected. What does the BIOS show?
Either way, the maximum amount of RAM you will be able to access (without
enabling PAE) is 3.2GB.

Enabling PAE does not help in 32bit Windows clients, but it does Servers
(Windows Server 2003 Enterprise Editions and later). See the Windows Memory
Limits table for details.
http://msdn.microsoft.com/en-us/libr..._windows_vista

"Doug" <Doug <> wrote in message
news:up$...
> (oops. "Reply Group")
>
>> How can I check to see if 4GB is being made available for the system to
>> utilize?
> It sounds like the RAM isn't being detected. What does the BIOS show?
> Either way, the maximum amount of RAM you will be able to access (without
> enabling PAE) is 3.2GB.

On Wed, 4 Jun 2008 21:40:57 +0100, "Doug" <Doug
<> wrote:

> > How can I check to see if 4GB is being made available for the system to
> > utilize?
> It sounds like the RAM isn't being detected. What does the BIOS show?


> Either way, the maximum amount of RAM you will be able to access (without
> enabling PAE) is 3.2GB.


Two points:

1. PAE doesn't help on Windows client operating systems, just on
servers.

2. The maximum accessible amount is not precisely 3.2GB, but varies
from as little as 2 to 2.5 (in rare cases) to as much as 3.5GB,
depending on your hardware configuration. Here's my standard post on
this subject:

All 32-bit versions of Windows (not just XP) have a 4GB address space.
That's the theoretical upper limit beyond which you can not go.

But you can't use the entire 4GB of address space. Even though you
have a 4GB address space, you can only use *around* 3.1GB of RAM.
That's because some of that space is used by hardware and is not
available to the operating system and applications. The amount you can
use varies, depending on what hardware you have installed, but can
range from as little as 2GB to as much as 3.5GB. It's usually around
3.1GB.

Note that the hardware is using the address *space*, not the actual
RAM itself. The rest of the RAM goes unused because there is no
address space to map it too.




--
Ken Blake, Microsoft MVP - Windows Desktop Experience
Please Reply to the Newsgroup

There is nothing in Windows itself that limits 32bit Windows from using 4GB
of memory. What limits Windows on modern hardware is the BIOS reserving
memory space for devices. It is called memory-mapped IO and provides a very
rapid but unprotected way of writing data to video cards, etc. The BIOS
reserves the memory space to protect it from the user programs from also
writing there. The whole idea is to get the fastest performace possible out
of things like video cards because that is what users want.

"churin" <> wrote in message
news:...
> Ken Blake, MVP wrote:
>> On Wed, 4 Jun 2008 21:40:57 +0100, "Doug" <Doug
>> <> wrote:
>>
>>>> How can I check to see if 4GB is being made available for the system to
>>>> utilize?
>>> It sounds like the RAM isn't being detected. What does the BIOS show?
>>
>>
>>> Either way, the maximum amount of RAM you will be able to access
>>> (without enabling PAE) is 3.2GB.
>>
>>
>> Two points:
>>
>> 1. PAE doesn't help on Windows client operating systems, just on
>> servers.
>>
>> 2. The maximum accessible amount is not precisely 3.2GB, but varies
>> from as little as 2 to 2.5 (in rare cases) to as much as 3.5GB,
>> depending on your hardware configuration. Here's my standard post on
>> this subject:
>>
>> All 32-bit versions of Windows (not just XP) have a 4GB address space.
>> That's the theoretical upper limit beyond which you can not go. But you
>> can't use the entire 4GB of address space. Even though you
>> have a 4GB address space, you can only use *around* 3.1GB of RAM.
>> That's because some of that space is used by hardware and is not
>> available to the operating system and applications. The amount you can
>> use varies, depending on what hardware you have installed, but can
>> range from as little as 2GB to as much as 3.5GB. It's usually around
>> 3.1GB. Note that the hardware is using the address *space*, not the
>> actual
>> RAM itself. The rest of the RAM goes unused because there is no
>> address space to map it too.
> Does the above mean as follows?
>
> BIOS and System|Properties show correct size of installed RAM while System
> Tools|System Information and Task Manager|Performance show the maximum
> usable part of the installed RAM. The maximum usable part could be as low
> as 2GB. Therefor,if 4GB is installed and Task Manager|Performance
> indicates that the Total Physical Memory is 2GB, then half of the
> installed RAM is waisted.

Ken Blake, MVP wrote:
> On Wed, 4 Jun 2008 21:40:57 +0100, "Doug" <Doug
> <> wrote:
>
>>> How can I check to see if 4GB is being made available for the system to
>>> utilize?
>> It sounds like the RAM isn't being detected. What does the BIOS show?
>
>
>> Either way, the maximum amount of RAM you will be able to access (without
>> enabling PAE) is 3.2GB.
>
>
> Two points:
>
> 1. PAE doesn't help on Windows client operating systems, just on
> servers.
>
> 2. The maximum accessible amount is not precisely 3.2GB, but varies
> from as little as 2 to 2.5 (in rare cases) to as much as 3.5GB,
> depending on your hardware configuration. Here's my standard post on
> this subject:
>
> All 32-bit versions of Windows (not just XP) have a 4GB address space.
> That's the theoretical upper limit beyond which you can not go.
>
> But you can't use the entire 4GB of address space. Even though you
> have a 4GB address space, you can only use *around* 3.1GB of RAM.
> That's because some of that space is used by hardware and is not
> available to the operating system and applications. The amount you can
> use varies, depending on what hardware you have installed, but can
> range from as little as 2GB to as much as 3.5GB. It's usually around
> 3.1GB.
>
> Note that the hardware is using the address *space*, not the actual
> RAM itself. The rest of the RAM goes unused because there is no
> address space to map it too.
>
Does the above mean as follows?

BIOS and System|Properties show correct size of installed RAM while
System Tools|System Information and Task Manager|Performance show the
maximum usable part of the installed RAM. The maximum usable part could
be as low as 2GB. Therefor,if 4GB is installed and Task
Manager|Performance indicates that the Total Physical Memory is 2GB,
then half of the installed RAM is waisted.