4GB RAM, only 3 show up in WinXP SP2

[Mark Levy]

Hi all,

I've just installed a new system with Windows XP SP2. I'm planning on using
this system as a VMWare host, so I need to get as much RAM into the system
as possible.

I purposely bought a system board that can take 4GB of RAM (and I checked to
make sure that WinXP will support 4GB as well).

The board is an Asus A8V Deluxe, with 4GB RAM, and an AMD Athalon 64 3500+
processor. While POST finds all 4GB of RAM, when I open the "General Tab"
from System Properties, it shows the processor, 3.00GB of RAM, "Physical
Address Extension." From within the "Performance" tab of Task Manager, it
shows a total physical memory of 3144932KB.

The system board documentation mentions that if you don't remap reserved
memory (for on-board devices) above 4GB, you will have reduced RAM
available, but I did that in the BIOS.

I can't find anything through google or in the MS knowledgebase. Any advice
would be very much appreciated.

Thanks,

Mark

 

[Ron Martell]

Hi all,

I've just installed a new system with Windows XP SP2. I'm planning on using
this system as a VMWare host, so I need to get as much RAM into the system
as possible.

I purposely bought a system board that can take 4GB of RAM (and I checked to
make sure that WinXP will support 4GB as well).

The board is an Asus A8V Deluxe, with 4GB RAM, and an AMD Athalon 64 3500+
processor. While POST finds all 4GB of RAM, when I open the "General Tab"
from System Properties, it shows the processor, 3.00GB of RAM, "Physical
Address Extension." From within the "Performance" tab of Task Manager, it
shows a total physical memory of 3144932KB.

The system board documentation mentions that if you don't remap reserved
memory (for on-board devices) above 4GB, you will have reduced RAM
available, but I did that in the BIOS.

I can't find anything through google or in the MS knowledgebase. Any advice
would be very much appreciated.

Thanks,

Mark

Use Start - Run - MSCONFIG, go to the BOOT.INI tab and click on the
Advanced Options button. Make certain that the checkbox for the
/MAXMEM= line is clear and that there is no value in the data box for
that line. Click on Apply and OK as needed to exit.

If you made any changes reboot the computer to put these changes into
effect.

Good luck


Ron Martell Duncan B.C. Canada
--
Microsoft MVP
On-Line Help Computer Service
http://onlinehelp.bc.ca

In memory of a dear friend Alex Nichol MVP
http://aumha.org/alex.htm

 

[Jerry]

See KB article 316739 on adding the switch /3GB to the boot.ini file.

 

[Jetro]

This motherboard supports no more than 4GB of RAM and you don't need neither
memory remap nor additional boot.ini switches kinda /3GB and /PAE which are
not relevant in your situation.

Original manual has nothing to say, but similar manual of A8V-E explains
that "Due to chipset resource allocation, the system may detect less than 4
GB of system memory when you installed four 1 GB DDR memory modules."
VIA chipsets aren't alone. The same effect inheres in Intel motherboards and
others. Try VIA 4-in-1 drivers.

 

[Mark Levy]

Damn... I really need that memory for some work I'll be doing using virtual
machines.

I've got a system with 3GB of RAM, and it's constantly running out of
memory. I bought this motherboard specifically to be able to use 4GB of
RAM.

I did install the latest VIA 4in1 drivers that I saw on the ASUS web site.
"May detect less than 4 GB..." Nice! Why don't they just say, "This
motherboard will only support 3GB of RAM when you waste your money on 4GB!

I guess I need to get on the vendor that sold it to me, as well as trying to
get someone at ASUS for some help.

Thanks,

Mark

 

[Mark Levy]

Thanks for the reply, but it was already set that way.

Thanks,

Mark

 

[Mark Levy]

Do you know if this is a HW problem with all versions of Windows, or is this
just a problem with WinXP?

I guess I could load Win2K server or Win2k3 server if it will allow me to
access the additional RAM, although there will be more memory being used for
services that I won't be using...

I suppose another option might be to try using Linux for the host OS, but I
would really rather not, plus I'd have to buy a new version of VMware, and
would not be able to use VirtualPC at all.

Thanks,

Mark

 

[Jetro]

I re-read the manual and found out that "When all four sockets are populated
with 1GB DIMMs (total 4GB), the system may detect only 3+GB due to the
Southbridge resource allocation". Weird, huh? Why only 4GB has an effect?
Because the reason is far from South Bridge:

1. Having all 4 slots populated CPU will automatically get RAM down to
DDR333.
2. Processor can recognize four unbuffered DIMMs but 6 sides of memory (3
per memory controller channel) of double-sided memory modules only. No
problem with single-sided modules.

Blame on AMD.

 

[Bob I]

Since the limitation is plainly stated, the problem is with the operator.

 

[Jetro]

LOL

 

[Mark Levy]

I re-read the manual and found out that "When all four sockets are populated
with 1GB DIMMs (total 4GB), the system may detect only 3+GB due to the
Southbridge resource allocation". Weird, huh? Why only 4GB has an effect?
Because the reason is far from South Bridge:

1. Having all 4 slots populated CPU will automatically get RAM down to
DDR333.
2. Processor can recognize four unbuffered DIMMs but 6 sides of memory (3
per memory controller channel) of double-sided memory modules only. No
problem with single-sided modules.

Blame on AMD.

This is the first chance that I've had to play around with the system
for a few days. Here are my observations.

When I had the remapping of the RAM enabled, while the memory was
counted during the POST, when I paused the system at the hardware
summary screen, just before boot, I noticed that it only recognized 3GB
of extended RAM. Again, while in Windows, System Information showed
only 3GB of RAM.

On a whim, I decided that I wanted to try disabling the remapping, and
the POST hw summary, now it did show 4GB of extended RAM. And in WinXP
System Information it now reports 3.68GB. It seems that when enabled,
the remapping maps the entire 4th GB of RAM over the 4GB boundery. In
addition to everything else, it looks like the system board that I was
sold is actually a v1 board, rather than v2, and I wonder if that's why
the 4th GB of RAM disappears.

I'm getting a bit peeved with the vendor who assured me that this would
be a system that would work with 4GB of RAM for my purposes.

Thanks,

Mark

 

[Clayton]

I had the same problem with an ASUS mb, I can't remember what model it was
but I put in 4X 512MB DDR400 and the board said it supports DDR400 but only
supported DDR333, after reading the manual it mentioned something about
single and doubled sided memory modules, maybe your modules are incorrect? I
find the Samsung memory is perfect for the ASUS motherboards

 

[Lester67]

Unless Asus is making the Dell GX280 motherboards, I don't know that I'
lay it all on them. I'm only able to access 2.99gb of a 4gb system.

The BIOS recognizes it, but XP won't.

(By the way, the knowlegebase reference - 316739, applies to Window
2003 Server, not XP.)

*Hi all,

I've just installed a new system with Windows XP SP2. I'm plannin
on using
this system as a VMWare host, so I need to get as much RAM into th
system
as possible.

I purposely bought a system board that can take 4GB of RAM (and
checked to
make sure that WinXP will support 4GB as well).

The board is an Asus A8V Deluxe, with 4GB RAM, and an AMD Athalon 6
3500+
processor. While POST finds all 4GB of RAM, when I open the "Genera
Tab"
from System Properties, it shows the processor, 3.00GB of RAM
"Physical
Address Extension." From within the "Performance" tab of Tas
Manager, it
shows a total physical memory of 3144932KB.

The system board documentation mentions that if you don't rema
reserved
memory (for on-board devices) above 4GB, you will have reduced RAM
available, but I did that in the BIOS.

I can't find anything through google or in the MS knowledgebase. An
advice
would be very much appreciated.

Thanks,

Mark

-
Lester6

 

[Steven Wabik]

i am very sorry to say but from what i know Windows XP only saupports up to
3GB of RAM.
i think i might know how to fix it though.
can you please tell me what version of Windows XP you have.

from,
Steven

 

[Jim Macklin]

XP supports up to 4 GB since 2^32 is 4 GB, but exactly how
the RAM is used varies with the mobo and the registry
settings. 4,294,967,296 bytes

BTW Windows 64 will support 2^64 or
18,446,744,073,709,551,616 bytes

Note, a 64bit system can address 4 billion times as much
RAM.

But you'll need a lot of money to buy that much until the
price comes way, WAY down.


--
The people think the Constitution protects their rights;
But government sees it as an obstacle to be overcome.
some support
http://www.usdoj.gov/olc/secondamendment2.htm




|i am very sorry to say but from what i know Windows XP only
saupports up to
| 3GB of RAM.
| i think i might know how to fix it though.
| can you please tell me what version of Windows XP you
have.
|
| from,
| Steven
|
| | >
| > Unless Asus is making the Dell GX280 motherboards, I
don't know that I'd
| > lay it all on them. I'm only able to access 2.99gb of a
4gb system.
| >
| > The BIOS recognizes it, but XP won't.
| >
| > (By the way, the knowlegebase reference - 316739,
applies to Windows
| > 2003 Server, not XP.)
| >
| > Mark Levy wrote:
| >> *Hi all,
| >>
| >> I've just installed a new system with Windows XP SP2.
I'm planning
| >> on using
| >> this system as a VMWare host, so I need to get as much
RAM into the
| >> system
| >> as possible.
| >>
| >> I purposely bought a system board that can take 4GB of
RAM (and I
| >> checked to
| >> make sure that WinXP will support 4GB as well).
| >>
| >> The board is an Asus A8V Deluxe, with 4GB RAM, and an
AMD Athalon 64
| >> 3500+
| >> processor. While POST finds all 4GB of RAM, when I
open the "General
| >> Tab"
| >> from System Properties, it shows the processor, 3.00GB
of RAM,
| >> "Physical
| >> Address Extension." From within the "Performance" tab
of Task
| >> Manager, it
| >> shows a total physical memory of 3144932KB.
| >>
| >> The system board documentation mentions that if you
don't remap
| >> reserved
| >> memory (for on-board devices) above 4GB, you will have
reduced RAM
| >> available, but I did that in the BIOS.
| >>
| >> I can't find anything through google or in the MS
knowledgebase. Any
| >> advice
| >> would be very much appreciated.
| >>
| >> Thanks,
| >>
| >> Mark *
| >
| >
| >
| > --
| > Lester67
|

------------------------------------------------------------------------

|
|

------------------------------------------------------------------------

| > View this thread: http://www.mcse.ms/message1518844.html
| >
|
|

 

[Jerry]

You have to edit the boot.ini file to add the switch /3GB on the line
starting XP. Do a Google search on boot.ini switches and you should find
explanations.

 

[Jetro]

Thoroughly read the manual: "When all four sockets are populated with 1GB
DIMMs (total 4GB), the system may detect only 3+GB due to the Southbridge
resource allocation". But the reasons are far away the Southbridge:

1. Having all 4 slots populated CPU will automatically get RAM down to
DDR333.
2. Processor can recognize four unbuffered DIMMs but 6 sides of memory (3
per memory controller channel) of double-sided memory modules only. No
problem with single-sided modules and this is what you need.