I have 3gb RAM, but XP only showing 2Gb?

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^ im thinking of geting another 2GB myslefe...even though only 3GB will be recognized/used...sicne i have already 2x1GB...but lately games take mroe than 2bg for me(about 2,260mb's)...with same mobo P5W DH Deluxe
 


ok too many ppl in here smoking crack or something, I have used both winxp, and vista 32-bit and have maxed it out with three 1Gb sticks, and I don't know whats all this fuss...All 3 sitcks show up, I don't like to fill up all the slots though, b/c sometimes some of the pc's i've worked with act funny when u max out the slots, so i never try to unless its necessary for some server or heavy memory user....

even when i max them out I've never had that kind of issue, at least not with 32 bit...
 
Well a good majority of people here are running 4 sticks, and besides having to worry about voltages, there also trying mix 1 gig sticks and 512 sticks.
 


I know silly, silly fools. :lol: :lol: :lol:
 




So then if you are running 4 sticks all in dual channel, they should all be either 512mb or 1gb? And not 2x512mb and 2x1gb?
 
2x 640MB 8800GTS' in SLI = 1280MB of addressable memory gone.

4000-1280 = ~2.7GB's left for ram, so if you are have 3GBs of ram, not all of the ram will be used.
 
Listen to Zorg, He is correct.
The_Monkey_Man is correct, On 4gig's. When 3 gigs are used the MIMO's are not loaded into Ram, However a small chunk is used for DOS enviorment.

Very good explanation.
www.dansdata.com/askdan00015.htm
 


That can't be because I have Vista with 4GB of RAM and a 8800GT with 512MB. Vista sees 3.5, but its apparent that the system would crash if the rest was just reserved for the video memory. Funny to mention here that most people always say 3Gb or 3.2GB at most, not sure what makes this so special but Vista really does see 3.5GB
 


"SLI MEMORY" is just a confusing branding for what memory manufacturers call "EPP" for enhanced performanc profiles. These are nothing more than extended SPD values that allow your system to configure a memory overclock for you. Advanced users would do better to manually set their memory overclock.
 


No, 2x 640MB = 640MB, at least in SLI mode. the memory map is the same between the two cards.
 


When i did my investigating into this with windows and mobo manufacturers they recommend running sticks with the same amount of ram, and the same manufacturer. Not trying to start a argument here, but I have seen lately more people trying to max out at 3 gigs with a 2x512 + 2x1gig have issues with either the os not recognizing the ram, or the computer not starting at all. Sure intel says its ok, but they dont make the os, so check and see what your os vendor has to say and then follow it, you might not end up like all the folks in here and actually get your ram recognized.
 
If the mobo sees it and it is not unstable then the OS should see it, assuming compliance with the ~3G limit explained in this link. I have seen a lot of problems with people using four identical sticks of 1G each, so the problems that you see with instability or no boot could be the mobo not accepting four sticks properly.

Maybe you could link me to anything that MS has to say on the subject.
 
Hi there, I just saw something very similar. I have a K8N DL motherboard (ASUS). I had 4Gb of RAM installed (winXP was showing 3.2 GB when I clicked on My computer, properties...). I installed a new video card today (the GeForce 9800 GX2). I noticed the system performance drop because paging was happening. I then noticed that Windows showed only 2GB of memory (same process, My Computer, Properties...)

Can someone please enlighten me?

Thanks in advance.
 
I'm having the same problem... Just got some new upgrades to my comp and after formatting I realized Windows XP Pro SP3 is only showing 2GB of my 3GB installed...

I have a eVGA x58 motherboard, 3x1GB Kingston RAM running tripple channel, an Intel i7 2.66ghz, and a Nvidia 8800GT 512mb.

Heres some screenshots of what windows and CPU-Z and the program that came with my motherboard are showing.

ram-1.jpg

ram-2.jpg

ram-3-cpuz.jpg



Windows and the motherboard program show only 2GB while CPU-Z shows the full 3GB... I downloaded another program that shows RAM usage and that only showed 2GB also...

Is my computer actually using all 3GB or just 2GB like Windows shows?
If you think it is using the full 3GB, is there a way I can be 100% sure?
 
so, i finally discovered that XP takes your new vid card's memory and allocates that amount from your RAM to it. so if you have 3Gigs of RAM, and have a gig vid card, then 3 minus 1 = 2 left over.

solution = vista 64 bit where the vid card does not require the parallel allocation. sorry, frustrating i know, but i ended up going back to my old vid card, rather than "upgrade" to vista.
 


Wrong. 32-bit OS's can only hold 2^32 (4GB) of memory addresses at any point in time. Basic mobo functions usually take up 256MB, leaving you with a max of 3.75GB. A 512MB GFX card leaves you with the famous 3.2GB left over.

64-Bit OS's behave the same way, only they have more space (2^64) than a 32-bt OS. Vista 64 still requires parallel allocation (as you call it), as the GFX card RAM still needs to be addressed by the OS. You simply have a few hundred thousand gigabytes to play with instead of just 4.
 
In a computer all bytes in the memory system need a unique name. This is called an address. For example, if you have 2 GB of main memory, then there are 2147483648 bytes of RAM in your machine, each of which require an address for the operating system to communicate to it. To give these all an address you need 31 bits to do it. Now, if/when you have 32 bits, you can name 4 GB (2 bytes to the 32nd power = 4GB).

This is why the total addressable space available in a 32 bit OS is 4GB – the OS runs out of addresses and cannot communicate/locate any more bytes of memory because of that.

You may think ”Hey, 4GB of address space… 4GB of RAM… What’s the problem” The problem is that memory isn’t the only thing needing an address. If you install a total of 4GB worth of RAM, the system will detect/use/display less than 4GB of total memory because of address space allocation for other critical functions, such as:

- System BIOS (including motherboard, add-on cards, etc..)
- Motherboards resources
- Memory mapped I/O
- Configuration for AGP/PCI-Ex/PCI
- Other memory allocations for PCI devices

Different onboard devices and different add-on cards (devices) will result of different total memory size. e.g. more PCI cards installed will require more memory resources, resulting of less memory free for other uses.

This limitation applies to most chipsets & Windows XP/Vista 32-bit version operating systems. Again, this is a limitation of the Operating System not having enough address space to allocate to the system *and* the RAM. Not allocating address space to devices renders them inoperable. Not allocating addresses to RAM simply results in the unaddressed section not being used in an otherwise fully functional computer. Therefore the OS designers assign RAM last.

We can have long debates about mathematical fundamentals and discussions about why the original Windows designers couldn't allocate the full theoretical max of 36 bits of address space so that users today would be able to use more resource. But at the end of the day, the designers and engineers 'Didn't Then'. So we 'Can't Now'.


If you install a Windows operating system, and if more than 3GB memory is required for your system, then the below conditions must be met:

1. A memory controller which supports memory swap functionality is used. The latest chipsets like Intel 975X, 955X, Nvidia NF4 SLI Intel Edition, Nvidia NF4 SLI X16, AMD K8 and newer architectures can support the memory swap function.

2. Installation of Windows XP Pro X64 Ed. (64-bit), Windows Vista 64, or other OS which can provide more than 4GB worth of address space.



Note: According to the latest Change Log published by Microsoft, Windows Vista 32bit SP1 will display the installed amount of RAM. This is a display change only.

 
ok... the address space =/= memory I understand

However I have 3Gb physical memory installed, Bios reports 3Gb, CPU-Z reports 3Gb, Crucial Memory Scanner reports 3Gb (and offered a nice price on upgrading to 4Gb). However Windows XP Media Center Edition v2002 SP3 resolutely claims I have 2Gb of memory....

I can't possibly be using 2Gb of address space for video/bios, so where is my 1Gb????
 
after much random poking at the BIOS I found that enabling software memory remapping around hardware hole (whatever that is) gives me 2.98Gb... good enough, although still miffed that that other halfs computer has always reported 3Gb (same setup, diff manufacturer, diff motherboard).

Motherboard is ASUS A8N-VM... a lot of google searching shows this is a common issue with this motherboard.
 
ok for anyone still having trouble try disabling your intagrated vidcard it freed the rest of my ram and now i have a solid 3gigs