4GB RAM reported as 2GB in XP SP2 (32bit)

[DimPrawn]

Hi folks,

I have a PC with 4GB ram installed (as reported by the bios).

Running Windows XP Pro (64Bit) OS, all 4GB is reported. However MS Virtual PC 2004 does not run on the 64 bit OS.

When runing Win XP Pro SP2 (32bit) OS, only 2GB is reported in msinfo32.exe, taskmanager etc.


Where's my other 2GB gone?

Worse than that, running multiple virtual PC 2004 instances on the box complains I don't have enough RAM, as it thinks I have only 2GB to play with.

How can I get to see the other 2GB of RAM?

[ASB]

It could be your boot.ini. I'm not going to suggest any changes but you could look here. http://www.pcbanter.net/showthread.php?t=807685

If it never boots again don't blame me.

For VPC I *think* Windows can only allocate 2GB to a process anyway (could be wrong).

I have had some issues with VMWare similar to that you describe. I can't remember how VPC manages multiple VM's but within VMWARE there are some memory configurations which can help, also if I try and start multiple VMs in one instance of VMWARE it often fails. Starting one VM in multiple instances of VMWARE generally sorts it. Also I have found with VMWARE that it's best not try try and start a second VM whilst the first one is starting up. This often provoke the "not enough memory" problem.

Only mention it because they do come from the same stable so it might be worth a try.

HTH

[DimPrawn]

The boot.ini options make sod all difference.

Question - running CPUID shows the RAM as 2GB (dual channel).

Does running 4 x 1GB DDR RAM sticks in Dual Channel mode effectively mean 2GB as far as the OS is concerned?

Is this why I have "lost" half my RAM?

I can't see any way in the BIOS to disable dual channel (it reports 4 x 1GB Dual Channel DDR400 RAM)

[threaded]

Win XP home cannot handle more than 2G, pro can handle 4G.

Try Pro.

HTH

[Joe Black]

"When runing Win XP Pro SP2 (32bit) OS, only 2GB is reported in msinfo32.exe, taskmanager etc."

Well spotted threaded!

[DimPrawn]

Win XP home cannot handle more than 2G, pro can handle 4G.

Try Pro.

HTH

Yes Threaded, LEARN TO READ before posting your usual mixture of ill informed drivel combined with lashings of bulltulip.

[threaded]

Oh just thought you didn't know what OS you were running.

Sorry for trying to help.

[jlrowe]

The most you can get is 3gb, you need to add the /3gb to your boot.ini - otherwise the max is 2gb.

The rest of the address space (either 2gb or 1gb) is used to memory map devices.

Roll on 64 bit windows...

[DimPrawn]

Roll on 64 bit windows...

That supports Virtual PC 2004.

[DimPrawn]

I only want to run Notepad.