XP Professional reports 2.99GB memory with 4GB installed?

I have an old XP Home vostro with 4gb ram and it
reports 3.75gb installed;

My new XP Professional vostro with 4gb installed
reports 2.99gb installed.

Maybe there isn't 4gb installed? Or is that the
default max for XP Pro.

Maybe the diagnostics would check actual installed
memory for me? Or maybe loading a linux live CD.

hmmm.
--


On the internet, nobody knows you're a jerk.

Try this as your search term in Google:

can windows xp use 4GB

Daddy

Ron Hardin wrote:
I have an old XP Home vostro with 4gb ram and it
reports 3.75gb installed;

My new XP Professional vostro with 4gb installed
reports 2.99gb installed.

Maybe there isn't 4gb installed? Or is that the
default max for XP Pro.

Maybe the diagnostics would check actual installed
memory for me? Or maybe loading a linux live CD.

hmmm.

Daddy wrote:

Try this as your search term in Google:

can windows xp use 4GB

Daddy

Ron Hardin wrote:
I have an old XP Home vostro with 4gb ram and it
reports 3.75gb installed;

My new XP Professional vostro with 4gb installed
reports 2.99gb installed.

Maybe there isn't 4gb installed? Or is that the
default max for XP Pro.

Maybe the diagnostics would check actual installed
memory for me? Or maybe loading a linux live CD.

hmmm.

It's not a question whether it can use it, but whether it's
installed.

I can always use it by dual booting linux someday.
--


On the internet, nobody knows you're a jerk.

the basic issue is that xp does have a 4gb maximum addressable memory space
which includes all memory addressed by the operating system - including such
as video memory, and other installed devices.
so if both machines have 4gb or ram installed and are reporting different
amounts in system properties it is probably because one of the machines has
more advanced options installed (ie a 512mb video card vs integrated video
reducing the amount of memory that windows reports by about 512mb), or might
have the pae switch enabled.
but there are many other issues at play including a physical address
extension (pae) option that can be set in certain machine to allow memory up
to 64gb to be address by a 32 bit version windows operating system... read a
better explanation of it all in these microsoft documents:
http://www.microsoft.com/whdc/system...AE/PAEmem.mspx
http://www.microsoft.com/whdc/system...e/default.mspx


"Ron Hardin" wrote in message
...
I have an old XP Home vostro with 4gb ram and it
reports 3.75gb installed;

My new XP Professional vostro with 4gb installed
reports 2.99gb installed.

Maybe there isn't 4gb installed? Or is that the
default max for XP Pro.

Maybe the diagnostics would check actual installed
memory for me? Or maybe loading a linux live CD.

hmmm.
--


On the internet, nobody knows you're a jerk.

"Ron Hardin" wrote in message
...
Daddy wrote:

Try this as your search term in Google:

can windows xp use 4GB

Daddy

Ron Hardin wrote:
I have an old XP Home vostro with 4gb ram and it
reports 3.75gb installed;

My new XP Professional vostro with 4gb installed
reports 2.99gb installed.

Maybe there isn't 4gb installed? Or is that the
default max for XP Pro.

Maybe the diagnostics would check actual installed
memory for me? Or maybe loading a linux live CD.

hmmm.

It's not a question whether it can use it, but whether it's
installed.

I can always use it by dual booting linux someday.
--


On the internet, nobody knows you're a jerk.

to check if it is installed simply enter the bios/setup program at boot and
check the configuration to see what the system recognizes as present.

You are seeing the effect of adapters having reserved blocks of memory in
the 4GB addressing range of a 32-bit CPU and a 32-bit OS.

Video cards can account for some of the difference, their RAM has to be
mapped in somewhere.

You can waste the memory (by ignoring what the computer cannot use while
leaving it installed) which may actually have some performance benefit if
the system is running in dual channel memory mode. You can install a 64-bit
OS--Linux, XP and Vista all have 64-bit flavors. Or you can remove some RAM
to stay under the limit.

William

William R. Walsh wrote:

You are seeing the effect of adapters having reserved blocks of memory in
the 4GB addressing range of a 32-bit CPU and a 32-bit OS.

Video cards can account for some of the difference, their RAM has to be
mapped in somewhere.

You can waste the memory (by ignoring what the computer cannot use while
leaving it installed) which may actually have some performance benefit if
the system is running in dual channel memory mode. You can install a 64-bit
OS--Linux, XP and Vista all have 64-bit flavors. Or you can remove some RAM
to stay under the limit.

William

I just wanted it to be there; regular linux can use it, or most of it, anyway more
than 3gb, since I paid an extra $40 for a refurb vostro to get it.

The curious thing was my XP Home system reports 3.5gb, where XP Pro reports only
3gb, for 4gb physically present ram. Assuming it's physically present.

The thing is busy copying from my old laptop to the new over the LAN, which takes
a few hours, so I can't experiment.
--


On the internet, nobody knows you're a jerk.

Christopher Muto wrote:
to check if it is installed simply enter the bios/setup program at boot and
check the configuration to see what the system recognizes as present.

Thanks, BIOS shows the correct 4096M.

Why XP Pro shows 3gb while XP Home shows 3.5gb for this amount remains
just one of those mysteries.
--


On the internet, nobody knows you're a jerk.

Hi!

I just wanted it to be there; regular linux can use it, or most of it,
anyway more than 3gb, since I paid an extra $40 for a refurb
vostro to get it.

That may not be the case. The memory is probably being reported
differently on Linux than it is Windows. Integrated hardware and
slotted adapters must be able to map themselves somewhere into the
system's total memory addressing space. This can't be ignored, because
the system will crash if its software just randomly stomps on memory
locations that may be in use. (Well, it can, but you and your software
will do so at the risk that the system may crash at any moment.)

I can reasonably assure you that your 4GB worth of RAM is properly
installed, and that the behavior you are seeing is definitely correct.
If you want to verify that, go into system setup, which will see and
report everything.

If you are going to run Linux, a 64-bit distribution will let you make
use of all the RAM you have paid for. Window XP and Vista come in 64-
bit versions as well, but if you use one, there exists the possibility
of not being able to find drivers for some of your hardware.

A 32-bit operating system will not be able to use all 4GB of installed
RAM due to the way your computer hardware works.

William

William R. Walsh wrote:

Hi!

I just wanted it to be there; regular linux can use it, or most of it,
anyway more than 3gb, since I paid an extra $40 for a refurb
vostro to get it.

That may not be the case. The memory is probably being reported
differently on Linux than it is Windows. Integrated hardware and
slotted adapters must be able to map themselves somewhere into the
system's total memory addressing space. This can't be ignored, because
the system will crash if its software just randomly stomps on memory
locations that may be in use. (Well, it can, but you and your software
will do so at the risk that the system may crash at any moment.)

I can reasonably assure you that your 4GB worth of RAM is properly
installed, and that the behavior you are seeing is definitely correct.
If you want to verify that, go into system setup, which will see and
report everything.

If you are going to run Linux, a 64-bit distribution will let you make
use of all the RAM you have paid for. Window XP and Vista come in 64-
bit versions as well, but if you use one, there exists the possibility
of not being able to find drivers for some of your hardware.

A 32-bit operating system will not be able to use all 4GB of installed
RAM due to the way your computer hardware works.

William

Ubuntu reports 3892912k physical memory (in top(1)) which, guessing that
k means 1024, is 3.7125gb, which is about what you'd expect if it used
everything not mapped to some device.

(On the older machine; so far I haven't installed linux on new ones since
Cygwin is perfectly fine under XP and the XP apps you get are a scale-tipper)
--


On the internet, nobody knows you're a jerk.