SLI Ram question during games

[xxcoop42xx]

hey guys in know this is wrong area but it kinda has to do with the fps of my gpu's so here it goes, i just installed 4GB of OCZ SLI RAM last night and windows vista 32-bit home premium see's all 4GB but 3dmark06 see's 2.5GB. thats fine (sorta) but i would like to know if the games i play have access to all 4GB or just the 2.5GB? all my games run beautifully smooth at 60 fps and never going below 45 fps. but i just dont know if the games can use all 4GB if they need to, so if any one could help me out that would be great and thanks much. my system specs are:

SLI GTX 260-216 oc'ed to 670/1110/1445
Q9300 oc'ed from 2.5 to 3.2GHz
4GB OCZ SLI Ram DDR2 Dual Channel @800MHz running in Dual Channel
780i SLI mobo

the games i play consist of:

Crysis/Warhead- never dropping below 45 fps/all very high settings and 4xAA
Far Cry 2- never dropping below 50 fps/all highest settings with 4xAA
Call Of Duty World at War - never dropping below 50 fps/all highest with 4xAA

so can they use all 4GB of my SLI ram? does running it in dual channel or having the SLI part on make it 2.5GB? thanks for any help.

 

[xxcoop42xx]

hey guys sorry for messed up first post,

i know this is in the wrong area but it kinda has to do with the fps of my gpu's so here it goes, i just installed 4GB of OCZ SLI RAM last night and windows vista 32-bit home premium see's all 4GB but 3dmark06 see's 2.5GB. thats fine (sorta) but i would like to know if the games i play have access to all 4GB or just the 2.5GB? all my games run beautifully smooth at 60 fps and never going below 45 fps. but i just dont know if the games can use all 4GB if they need to, so if any one could help me out that would be great and thanks much. my system specs are:

SLI GTX 260-216 oc'ed to 670/1110/1445
Q9300 oc'ed from 2.5 to 3.2GHz
4GB OCZ SLI Ram DDR2 Dual Channel @800MHz running in Dual Channel
780i SLI mobo

the games i play consist of:
Crysis/Warhead- never dropping below 45 fps/all very high settings and 4xAA
Far Cry 2- never dropping below 50 fps/all highest settings with 4xAA
Call Of Duty World at War - never dropping below 50 fps/all highest with 4xAA

so can they use all 4GB of my SLI ram? does running it in dual channel or having the SLI part on make it 2.5GB? thanks for any help. also what is pagefile memory and why does 3dmark06 show i have 5.21GB of that?

 

[zodiacfml]

they don't.
there is no application or game that can address more than 2.5 GB of ram unless it is a true 64bit application running on 64bit vista.
4GB is only useful if you leave applications opened at the same time.

don't worry about the dual channel config, you get all that dual channel memory bandwidth.

pagefile memory is a memory using your harddisk. don't bother with it unless you want to prevent it from using that 5GB of data.

 

[xxcoop42xx]

ok another question about my ram, when i had dell 3GB ram installed before the SLI ram why did 3dmark06 see 3GB and not 2.5GB like now?

 

[jitpublisher]

A 32 bit OS can address 4 gig of memory. That includes all the memory in your system, including memory on your video cards, CPU cache, HDD cache, contollers, etc., ALL of it. All these are assigned memory space first, whatever is left over to make a total of 4 gig is assigned to RAM. When you had your Dell, I assume you were not running 2 cards in SLI with 512meg of memory each, thus you had 3 gig of main memory to use. Now that you have added another card with 512meg of memory, tada! now you only have 2.5gig of RAM left for addressing. Is this what has happened? If not let us know, it could be something else, make sure you have memory remapping enabled in your BIOS......
By the way, "SLI" memory is merely a marketing gimmick. SLI memory is no different than any other memory, except that nVidia endorses it so they get a nifty little kickback from the memory manufacturer.

 

[xxcoop42xx]

ok so what im getting out of you guy's answers is i have 4GB of ram and it is/can be used but its just spread out across different things. the dell i still have/use, its a XPS 630i, i just did a major overhaul on it though because the dell parts sucked. i added a new mobo, a better cpu cooler, added 2x GTX 260-216 and changed the RAM. so what im getting is even though it tells me 2.5GB it really is 4GB but its split up around the pc. is that what your saying? im not having any issues with it, my games run maxed out and everything is loading waaay faster and i get no slow downs or anything since i added the SLI ram. the GTX 260-216 have 896mb each. and thanks for your help so far

 

[jitpublisher]

No, it is not using all of your memory at all. It is only able to use exactly what it says, 2.5 gig.
I am not sure you are understanding completely. The 4 gig is not split up around your PC. The memory on your video cards for instance together is nearly 1.8 gig by itself. Your OS has to "make room" and use this memory, or address it. When the OS loads, all of this other memory, and we are not talking about your main memory, is addressed or used, or accounted for first. After all this is done, the OS then addresses what it can, of your ram. Since it already is addressing about 1.8 gig of memory in your system, all that is left it can address of your RAM is about 2.3-2.5 gig. (it is not exact because of the way the memory is actually read and and accounted for) The rest of your installed main memory, or RAM is just sitting there, unable to be used for anything.
If you want to break the 4 gig memory limit, you have to have a 64 bit OS.
Then all the memory in your PC can addressed, as well as all of your RAM, so that you would then have 4 gig of RAM showing, and capable of being used.

 

[xxcoop42xx]

oh ok, thanks for the info. looks like i might upgrade to 64-bit in a while