Vista 32 only sees 2GB of 4GB RAM

copsey · 18 Apr 2007 at 09:21

Guys - my shiny new vista box rocks but I'm only seeing 2GB out of the 4GB RAM. I've done the memory remap in the bios so that it sees 4gb. I understood that I should be seeing 3GB due to the graphics card, etc, taking some of the address space (8800 GTX - 768MB). Is that taking me down to 2GB or is somehting else wrong?

I used vista boot pro to set the PAE switch and DEP is on too.

Help!!

MeatLoaf · 18 Apr 2007 at 09:32

I was under the impression you needed Vista 64 bit to see 4gb

Stelly · 18 Apr 2007 at 09:34

nope you can run in either 32 or 64 dont need 64 exclusively... could it be your motherboard??

Stelly

copsey · 18 Apr 2007 at 09:35

The bios shows 4gb... so i don't think its the mb.

Does vista 64bit run everything ok? I was under the impression nothing runs on it - games, etc.

Stelly · 18 Apr 2007 at 09:36

but like you said there is a problem see below with windows and 4Gb of memory

http://www.planetamd64.com/lofiversion/index.php/t27818.html

http://blogs.msdn.com/hiltonl/archive/2007/04/13/the-3gb-not-4gb-ram-problem.aspx

Stelly

copsey · 18 Apr 2007 at 10:01

I don't expect to see the full 4gb, but surely I shouldn't' be seeing exactly 2?

I should be seeing 3 or 3.2 or something...

ubern00b · 18 Apr 2007 at 12:14

http://msdn2.microsoft.com/en-gb/library/aa366778.aspx

Just FYI

copsey · 18 Apr 2007 at 13:30

Nice one - looks like this might be the ticket:

BCDEDIT /set increaseuserva 3072

(from http://www.vista64.net/forums/vista-general/39930-adding-3gb-switch-vista.html)

Question is, does this mean that my GTX is going to end up with less memory or something weird like that? Seeing as i'm reducing the amount of memory addressable by the system.

ubern00b · 18 Apr 2007 at 14:18

I dont really understand the whole "reserved for system peripherals" thing as the GTX or any vid card has its own onbard memory, it doesnt use system ram at all. Only onboard or "turbocache" type devices share system ram.

stickroad · 18 Apr 2007 at 15:16

Ok i CAN NOT find a definite answer, Does 32bit O/S USE 4GB,NOT SEE IT USE IT?

Theirs so many diffrnet answers on this.

Pulseammo · 18 Apr 2007 at 15:38

ubern00b said:
I dont really understand the whole "reserved for system peripherals" thing as the GTX or any vid card has its own onbard memory, it doesnt use system ram at all. Only onboard or "turbocache" type devices share system ram.

http://en.wikipedia.org/wiki/Memory-mapped_IO

stickroad said:
Ok i CAN NOT find a definite answer, Does 32bit O/S USE 4GB,NOT SEE IT USE IT?

Theirs so many diffrnet answers on this.

Taking into account the ~1/2 - 3/4 gb of space that the operating system steals for memory mapped IO you should be able to see 3gb-ish in some way or another (Don't ask me how, I'm just sayings its theoretically possible

). The system cant really take more than 4gb of ram though as 2^32 (its a 32bit OS) is 4GB.

P.S What do you mean by "see" and "use"? The OS cant "see" more than 4gb because of a hardware limitation, it cant "use" (well actually it can use it all its just YOU cant for user mode stuff) more than around 3gb for user mode stuff.

Yellowbeard · 18 Apr 2007 at 16:29

Vista 32 bit has the same limitations as XP 32 bit with regards to memory allocation. Vista is not a "magic bullet". You will need a 64bit OS to "fully" utilize 4gb of memory for applications.

copsey · 19 Apr 2007 at 09:19

the extender user va thing didn't work.

I think the PAE switch should have... but doesn't.

wrighty83uk · 19 Apr 2007 at 12:29

Hi all

dont know if this is relevant but i have 4 gig sticks of memory, i use vista 64bit and it only shows 3.25gig! its really annoying... have been told thats all that vista can use however by my local "expert"

Yellowbeard · 19 Apr 2007 at 14:32

wrighty83uk said:
Hi all

dont know if this is relevant but i have 4 gig sticks of memory, i use vista 64bit and it only shows 3.25gig! its really annoying... have been told thats all that vista can use however by my local "expert"

I'm guessing you have either a 512mb or 768mb video card?

copsey · 19 Apr 2007 at 15:45

So Yellowbeard how come I'm only showing 2GB??

Combat squirrel · 20 Apr 2007 at 10:55

Right long and short of it is:

1) It will only see 3gb anyways (GET VISTA 64bit!!)

2) Some of your ram is either duff or not installed into the board properly

3) 32bit Vista may limit it to 2gb as 32bit OS's are known to be a lil unstable when you have more ram than they can address

copsey · 20 Apr 2007 at 11:00

Vista 64 "doesn't work" with anything though, I thought?

BIOS sees the full 4GB BTW.

thanks though

Yellowbeard · 20 Apr 2007 at 11:14

Do you have a 512mb or 768mb video card?

copsey · 20 Apr 2007 at 11:17

768 - if you're going to tell me that its eating into the address space, what I don't understand is why i'm seeing 2GB on the button, rather than 2.3 or something... or does it just round it to 256 MB chunks or something??