XP, RAM and virtual machines

ringo747 · 15 Jun 2009 at 14:30

recently i stuck 4gb ram in my laptop running xp. In bios it shows up as 4gb, in my computer properties it shows as 2.99gb. I am curious to know if i can use the other 'hidden' 1gb for running my virtual machines? Ideally i'd like to have 2gb for the host and 2gb for the virtual machines. I have read many threads about not seeing the full 4gb in xp but wondered is it still useable even though the total is 2.99?

Burnsy2023 · 15 Jun 2009 at 14:38

ringo747 said:
recently i stuck 4gb ram in my laptop running xp. In bios it shows up as 4gb, in my computer properties it shows as 2.99gb. I am curious to know if i can use the other 'hidden' 1gb for running my virtual machines? Ideally i'd like to have 2gb for the host and 2gb for the virtual machines. I have read many threads about not seeing the full 4gb in xp but wondered is it still useable even though the total is 2.99?

No, you can't use the rest of the RAM on XP 32bit. You'll need to use a 64bit OS like XP x64, Vista x64 of the 7 x64 RC.

ringo747 · 15 Jun 2009 at 14:41

Cheers for that. I had expected to see maybe 3.5GB in the properties window but maybe 2.99 is normal for having 4gb installed.

zetec452 · 15 Jun 2009 at 14:46

You on XP SP3? I thought it showed the full amount on SP3? I could be wrong.

ringo747 · 15 Jun 2009 at 14:50

Am on sp3 as of the other day.

Burnsy2023 · 15 Jun 2009 at 15:02

JonRohan said:
You on XP SP3? I thought it showed the full amount on SP3? I could be wrong.

It will report 4GB, but use the same amount as any previous SP. I've seen machines with 4GB ram see less than 2GB RAMwith a meaty SLi setup.

ringo747 · 15 Jun 2009 at 15:07

Burnsy2023 said:
It will report 4GB, but use the same amount as any previous SP. I've seen machines with 4GB ram see less than 2GB RAMwith a meaty SLi setup.

Do you mean report 4gb within the system properties window? If that is the case then im not sure why im still only seeing 2.99GB

Burnsy2023 · 15 Jun 2009 at 15:22

ringo747 said:
Do you mean report 4gb within the system properties window? If that is the case then im not sure why im still only seeing 2.99GB

Yes I do mean that. but TBH it doesn't make any difference anyway.

monkeyspank · 15 Jun 2009 at 15:29

Should be able to use 3.5GB but your laptop might be using 0.5GB as shared video memory or something, leaving you with 3 ??

Burnsy2023 · 15 Jun 2009 at 16:01

monkeyspank said:
Should be able to use 3.5GB but your laptop might be using 0.5GB as shared video memory or something, leaving you with 3 ??

Not quite. THe amount of total physical memory a 32bit OS can handle is 4GB.

The amount of RAM shown is dependant on the number of devices that require their physical memory (VRAM, caches and registers) to be addressed.

So if you have a graphics card with 1GB VRAM (4GB - 1GB = 3GB), and 3 HDDs with a 32MB cache (3GB - 92MB = 2980MB), a RAID controller with 128MB cache (2980MB - 128MB = 2852) and various other system devices, the amount of address space left for system RAM is greatly diminished.