Windows Vista Vista RAM limit ?

Vista Ultimate, 32 bit, recognizes 2Gb of my Corsair Dominator 1066Mhz. And in the setup FSB/Memory Config, I have enabled SLI memory and it shows up in the NVidia Display page from Control Panel.
But when I added 2 Gb more of SLI-ready Ram at 1066 ( SLI-ready Dual channel, same exact ram except its OC brand, not Corsair, Vista still only finds 2 Gb. And the SLI - Ready memory does not show up to be enabled.
I have 2 NVidia 8800 GTX video cards installed, but have been unable to link them in an SLI config.
After numerous crashes and black screen problems, the latest NVidia driver patches for Vista seem to have solved the crashes, but still having trouble enabling SLI.
I heard that Vista is unable to use more than 3 Gb of RAM. Is this true ?
Also, since the 1Gb Ram chips come in Dual Channel, how can I use only 3 ? Seems like I'd need either 2 Gb or 4?
To make matters more confusing, at boot-up, the text before Windows loads shows the memory test okaying all 4 Gb when the OC RAM is installed, but Vista still shows only 2 available to it. And when all 4 are in, SLI-Ready memory is not found at all, even though all 4 are 1066 Mhx SLI_Ready Dual channel RAM modules.
Anyone have advice ?

Andy

 

Hi, probably the best place to try and find out is the motherboard manual or the FAQs at the m/b manufacturer's website.

The m/b may have a maximum size limit on RAM at 4GB and it may be stipulated that the RAM be all the same make and model. It may require 2 X 2GB modules.
For different brands, 3GB may be the limit and that could work with 2 X 1GB and 2 X 512MB modules. You are also involving the "sharing" with the SLI.

If you are working at the limit of the OS or motherboard's capabilities don't be surprised if things don't work as expected

Matt

 

Ram Limit on Vista ?

Thank you Mattman for the nice replyand goodadvice. I checked the M/b manual as you suggested. (nforce 680i SLI Mainboard.)
It supports up to 8Gb of DDR2 memory & supports SLI-Ready memory up to 1200 MHz. So my 4Gb of 1066MHz should be fine. I have a total of 4 ram spots to fill. The 2 - 1Gb Corsairs are in slots 0 and 1 ( non-adjacent, as required ).
So that is no problem. However, your comment about the 4 ram modules maybe needing to be the exact same , got me to thinking that maybe the Corsair & the OC brands are not identical, even though the specs are identical and the salesman at Tiger Online assured me that they were compatible.
I believe you may have hit the nail on the head. When I run with the 2- 1 Gb corsairs, all is fine. But adding the additional 2 OC brand 1-Gb modules of ram does several things :
1. Increases my Vista Performance score from 5.3 to 5.4 ( small but noticeable increase)
2. Results in the "SLI-Ready Memory Found" text disappearing in the Setup/ FSB/Memory section.
3. Results in the " Enable SLI" text disappearing from the nVidia Setup Icon in control panel. SLI memory apparently is no longer found when the OC is added to the corsair RAM.
4. And yet, at bootup, before Windows Vista 32 Ultimate loads, the memory self-check text shows FOUR (4) Gb of ram, and checks "ok" .

Therefore, as you speculated, perhaps the 2 brands are incompatible on this m/b with Vista. ( Why the 4 are found by the PC but not Vista still perplexes me).

So before I invest in high priced ram and buy another set of Corsair Dominator DDR2 1066 modules, I have 2 questions:

1. Do I need the extra ram or is 2Gb enough for my gaming machine?
2. IS there a Vista 32 Ram limit of 3 Gb and if so, since I have 4 available dimm slots, would the 2 Corsair 1 Gb modules work ok with an additional 2 512 Mb modules for a total of 3 Gb ram ? Or would 4 -1 mb Corsairs be found by Vista?
Obviously looking to the future, I would rather have 4Gb than 3Gb, if I'm going to later need to upgrade.

Again TY for your input.

 

Follow up to Vista RAM limit

I just came from Tiger Direct Website, looking for Corsair RAM. I need to add to my 2 one Gb memory modules: Corsair XMS-2-8505 @ 1066 MHz. The 2 modules I have in my Vista 32 bit OS (Ultimate version) are 8500 C5D models.
However, while browsing I came across a 4 Gb set that contains 4 - 1 Gb modules.
The below cut & pasted warning was attached to the sale ad:

"[FONT= "Arial Black"]Please note: Installing 4GB onto PCs with 32-bit operating systems is not advised since 32-bit operating systems do not support 4GB of system memory[/FONT]. "

WOW ! I have been searching and asking everywhere for this info. Does no one know about this ? I sure didn't although I had heard "rumors" that Vista only supported 3 Gb of RAM.

 

Hi Andy,

Yes, the limit for 32 bit systems is 4GB, BUT if they can use a system called PAE, they can address larger amounts. So if the question is can 32bit system run more than 4GB, the answer is yes, but not Win XP or Vista. Clear as mud?
http://support.microsoft.com/kb/555223
Does not include Vista.
http://www.computerworld.com/printthis/2006/0,4814,107597,00.html

I have seen discussions where Vista only recognises 3GB, apparently yours will only recognise 2GB and that may be influenced by the SLI involvement.

Motherboard manufacturers stipulate how the RAM must be installed. This morning I saw the information I have attached below.
Note:

It stipulates that the modules need to be identical to run 4 X 1GB modules. I suppose the same brand and model should be identical enough

nVidia is not the manufacturer of the motherboard, only the chipset. You will need to look at the motherboard manual or go to the manufacturer's website and look up your motherboard model.

Would 2Gb of RAM be enough? Check the System Requirements of the program you wish to run. If it requires that you have 2GB and you are running 2GB, close down any other programs before running it. (When games were DOS-based, people would boot into DOS to allow full resources to the game).

3GB of RAM might be ideal if you cannot satisfy the "identical" requirements (and it would probably run best if you found similar Corsair modules in 512MB).

Mix and match can work sometimes with RAM, probably not though when you are working at the "limits ".

Matt

 

Vista 32 bit RAM limit

Again, TY very much for input, Matt.

My m/b is an EVGA brand nForce 680i SLI Mainboard. Since I don't wish to buy all new RAM ( the 2 Corsair Dominators are Extreme Performance 1066 high end DDR2 RAM ) and since the lowest configuration is 1 Gb, in 2 module packages for a 2 Gb total, no 512's in this speed, I guess I will plug along with a mere 2 Gb of RAM forever. lol
As I read the manual, I see the m/b would easily support 8 Gb RAM, but good old Vista , can't use it.
Being Dual channel, I would need 2 more identical Corsairs... so I can't even get 3 Gb RAM without tossing out all my present, and starting with slower memory in 512 sizes ( 1 Gb, 1 Gb, 512Mb, 512 Mb). This 3 Gb of slower ram probably would be a little better than 2 Gb of extreme ram, but not by much.
So at least, thanks to you, I have learned something today.
My Win XP Pro never gave me any trouble. Vista, however, has been a pain since I got the new PC and had to get it as the OS. Finally, after 3 months of headaches, the graphics drivers are Vista patched and stable . But it was a frustrating time while the third party companies frantically tried to make stuff work on this new , too soon released beta OS that Microsoft thrust on us.
Don't misunderstand, Vista has some great potential, the Direct X 10 being a vast improvement, and I love the Performance check, etc, but the reliability and time tested stability of XP is still not quite there.
Happy holidays & I appreciate your help.
Andy