Holy SLI 7800GTX = System Memory Hog

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Ackmed

Diamond Member
Oct 1, 2003
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Again, it is NOT the SLI'd cards. If this were true, it would be very well known. I have the exact same amount of ram after adding another card, and so does all others Ive seen. Its something on your system, bios, OS, etc.
 

papaHesch

Member
Aug 24, 2005
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I agree with that but it is defiantly not the OS because it happens at post vs boot time. I just do not see any config in the BIOS that causes a change. I will try removing the ram later and see if the problem still occurs.

Papah
 

Ackmed

Diamond Member
Oct 1, 2003
8,499
560
126
Check for a new BIOS, or just reset it perhaps. Im on a DFI NF4 with no problems like you describe.
 

Steve

Lifer
May 2, 2004
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Originally posted by: phantom404
Strange...I have 2gig of Ram and windows shows 2 gigs of ram. Never seen your problem before and I'm running 2 GTX KOs.

Anybody running less than 4GB of RAM won't see this phenonenon as is Windows will address the hardware in virtual memory.
 

Steve

Lifer
May 2, 2004
15,945
11
81
Originally posted by: papaHesch
I agree with that but it is defiantly not the OS because it happens at post vs boot time. I just do not see any config in the BIOS that causes a change. I will try removing the ram later and see if the problem still occurs.

Papah

Is there a Memory Hole/Remap option in your BIOS?
 

papaHesch

Member
Aug 24, 2005
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am8000,

Have a 4g remapping option for hardware and software in the bios. I have tried enabling both of the options with no change in the posted memory, defiantly weird.

papah
 

papaHesch

Member
Aug 24, 2005
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Update on this thread:

Well after searching long a hard across the web; I am actually not the only one. There are a couple other souls in pain also. Of course when I remove either the two 1 GB sticks or the two 512MB sticks for a total of 2 GB or 1GB of total system memory, then the posted 2GB or 1GB is available to system and OS. Basically the Bios tells me it has 2GB and 2GB are available. The OS also posts the correct amount in XP32/XP64. This of course leads me to believe this is either a memory controller problem or BIOS problem with trying to use 32bit addressing and with AMD I believe using 128bit memory controllers I can not understand this. But what I can not figure out is why the BIOS would not use the top of the memory address stack for the video cards and devices. Why would the BIOS use the 2GB to 3GB range when I have the 3GB to 4GB range available? I also found a great white paper on this subject if anyone is interested. Anyone have any information to add please do.

Thanks,
Papah
 

kamranziadar

Banned
Aug 20, 2004
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Originally posted by: papaHesch
Update on this thread:

Well after searching long a hard across the web; I am actually not the only one. There are a couple other souls in pain also. Of course when I remove either the two 1 GB sticks or the two 512MB sticks for a total of 2 GB or 1GB of total system memory, then the posted 2GB or 1GB is available to system and OS. Basically the Bios tells me it has 2GB and 2GB are available. The OS also posts the correct amount in XP32/XP64. This of course leads me to believe this is either a memory controller problem or BIOS problem with trying to use 32bit addressing and with AMD I believe using 128bit memory controllers I can not understand this. But what I can not figure out is why the BIOS would not use the top of the memory address stack for the video cards and devices. Why would the BIOS use the 2GB to 3GB range when I have the 3GB to 4GB range available? I also found a great white paper on this subject if anyone is interested. Anyone have any information to add please do.

Thanks,
Papah


So after removing 2GIGs you have 2gigs in your system, and it works fine?
 

papaHesch

Member
Aug 24, 2005
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Yes, and thus making the extra giga of ram worthless at this time. The problem is I use this computer for two things: games and photo video editing. The extra gig makes a huge difference in performance and my life easier. I use to have 4GB of total memory but the BIOS did the same thing and gave me a 4GB total and ~2.35GB available memory with the 4G remapping turned off. If I turned on 4G remapping the BIOS I could see the full 4GB in the BIOS for total and available memory at post but my SCSI controller would throw-up all over me. This leads me to believe one of three things is happening:
1)MSI cards have some sort of weird static memory address map for the address from 2.35GB to 3.GB. This is the least likely answer because I would have to shot somebody at MSI.
2) AMD memory controllers do not like 4 sticks in certain situations. I have tried down-tunning the memory to DDR333 and up the timings across the board with no results. Some people on the AMD forum have experienced this problem with 4GB.
3)Asus's BIOS is causing the problem by not allowing the MSI cards to map their memory address above 3GB because they have some flaky code that maps all the devices addresses above 2GB unless you have 4GB (vs. 3GB) of memory. Then the 4G remapping will work in theory. I have found no way to get a device to statically map to a memory address of my choosing above 3GB. I believe the problem is somewhere in the BIOS code for the a8n-sli Premium but it will be a real pain to get it solved.

Moral of the story is either stick with 2GB or 4GB and fight your way to getting it to work. 3GB though is a waist of your money in SLI on an ASUS board


papah
 

Steelski

Senior member
Feb 16, 2005
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take out one of the sticks of 512 MB and tell us what you seel. it should post more ram than 2.4 gig......if thats the case then its the interaction of your motherboard with your AMD processor. the newer ones dont have a problem at 333 timing but not certain for 400mhz speed. try setting the timing to t2 , not t1, that might also have an effect. I know that the ATI motherboards dont have a problem with this but i have heard this to be the case with the Nvidia ones when running 4 sticks of ram, especially when they are not the same.
 

Leper Messiah

Banned
Dec 13, 2004
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thats weird. Most people don't have over 2 GB of ram though, so they probably didn't even realize there was a problem.


What Do you need 3GB of ram though for?
 

papaHesch

Member
Aug 24, 2005
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Steelski,

I have tried ddr333 at 2t (can got get the computer to boot at 1t with 4 sticks which is common) but I have not tried to mismatch the memory. I will try this out and see what happens after dinner. The memory is also the same brand and model with different sizes (patriot LL ddr). I actually checked the chips and they both are infenion.

Leper Messiah,

I use the computer for games and photo/video editing. The later uses memory like a sailor drinks rum on leave. There is a noticeable differnece between 2 to 3 GB with these apps. Games not so much if anything.

papah
 

papaHesch

Member
Aug 24, 2005
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Steelski,

I pulled one of the 512MB memory sticks and the following was posted by the Bios: total=2.560GB and available=2.304GB. As you thought it is the interaction of the Motherboard and the processor. I have tried about every memory timing possible (ddr333, ddr200, 3cas) and is their anything else in the BIOS config I should try? Do you think it would help to try 4GB over 3GB? I use to have 4GB but had a problem with a PCI SCSI Raid controller pucking if I used 4G remapping. Without the 4GB remapping I got the same results as I am with 3GB. I have a pci-e SCSI controller know and it might be a little more forgiving.

papah
 

papaHesch

Member
Aug 24, 2005
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Originally posted by: Vegito
http://pics.bbzzdd.com/users/forcesho/4gb.JPG

Heres the chart..

I got 4gb.. its too bad my board can't take 2gb memory.. i would have 8.. memory is cheap (to me) plus i'm running VMs with some adobe work so having as much memory as possible is good for me

Vegito,

The chart is not giving me hope and I assume this is memory address allocation for a 32 but architecture, am I correct? Basically to me it says that 3GB of system memory on a 32 bit architecture (i.e. XP32) is as good as 4GB. The problem I am having is imganing that the memory hole starts at 3GB and it slowly trickles down to 2GB after all the devices, video cards, and etc. Part of the reason why I went with 3GB of memory is because most of my world is still 32 bit even though I run XP64. I am still having problems figuring out why this board starts the memory addressing at 3GB vs. 4GB. Do you know of a way to see all the memory addresses being used by the motherboard? I can look in device manager but I am looking for something a little more concrete. That way I can hammer asus to fix this problem. Do you also think it would help to go back to 4GB and use the 4G remapping option? Did this work for you?

Thanks,
Papah
 

Patrick Wolf

Platinum Member
Jan 5, 2005
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Originally posted by: papaHesch
Nextman,

Usually use headphones for audio and have been reasonably satisfied with average HD/EAX audio on the board. I want to hear the new x2 board from creative but have not seen a demo computer with it on. Christmas is around the corner and if the sound is considerably better I might go for it. I am usually more concerned with raw speed, silence, and graphics and thus sound is the last thing I spend money on. Thanks for the complement.
If I understand correctly, you have an X-Fi soundcard (listed on your Rig page) and your not using it? If your interested in raw speed than use that soundcard, it takes a lot of load of the CPU. And the sound quality of onboard compared to an X-Fi? Forget about it! The X-Fi will blow your crappy onboard out of the water! And the X-Fi is supposed to be really awesome with headphones. YOU MUST USE/GET A X-Fi SOUNDCARD.
 

papaHesch

Member
Aug 24, 2005
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Patrick,

Got this thing for my birthday a week ago and I use it over the onboard sound. It defiantly sounds better then the realtek and I am getting an extra couple fps in most games. I was not going to get one of these but t defiantly sounds substantially better with headphones. I was impressed.
 

Steelski

Senior member
Feb 16, 2005
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ok.
Now we see what the problem is then we need to find a solution. I am looking around as much as possible. But personally i wouldent bother with three gig. only a couple of games take advantage of it at the moment. if you are doing something more serious than games then please say what but trust me you will be just as well of with the two 1gig sticks.
 

Steelski

Senior member
Feb 16, 2005
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what can you tell us about the processor. is it 130nm 90nm?
Winchester, Venice, San diego core?
i know for a fact that the winchester cores have a bug that does not let them interact with more than 3 sticks effectively.
 

papaHesch

Member
Aug 24, 2005
67
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0
Steelski,

I have an AMD X2 4400 @ 90nm - Toledo - Revision JH-E6. Should have 6 steps with the E6 revision and two of my memory sticks are double sided (1GB) and two are single sided (512MB) in physical design. Called Patriot and they said the models are dual and single bank respectively to their physical layout (I am not sure still). Thus, this should squeze into the 6 steps the memory controller on AMD CPU has I believe. Plus from what I have read, and someone correct me if I am wrong, if I had a total of 8 banks with my memory then the CPU and MBoard would only see six of the banks. Thus, you would only post like 2.5GB vs 3GB of total memory not available.

Thanks for the help,
Papah
 

Peter

Elite Member
Oct 15, 1999
9,640
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Guys, I said it before, and I'll say it again: The "missing" RAM is not due to any problem with the RAM or the RAM controller. It's for the simple fact that EVERYTHING has to fit inside the first 4 GBytes of SYSTEM ADDRESS SPACE: RAM, graphics card memory, all other I/O, AGP aperture if any, and misc system essential hardware like BIOS ROM, interrupt controllers, timers etc.

The more of that I/O stuff you have, the less RAM will get _mapped_ to become available. How much RAM the RAM controller presents is irrelevant to this limitation.
This is very much like waaaaay back in the PC-AT days, you could very well put 1 MByte of RAM into the machine and still see only 640KB in DOS.
Same thing - only this time the address size limit is 32-bit, not 20-bit.

And no, this is not due to some obscure (and entirely made up) issue with "six steps in the memory controller" (wtf?) or a 128-bit-WIDE memory controller not being able of something.

It is because the system is, overall, running out of space to map things. Something has to give, and it's the amount of _available_ RAM.
 

papaHesch

Member
Aug 24, 2005
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Peter,

I would usually agree but what could possibly be using almost 2GB of memory addresses? Why when I have only three sticks (2* 1GB sticks and a 512MB stick) does the system post 2.5 GB vs 2.3GB with 4 sticks. I have done the math with all the devices in my computer (got the space used from a technical white paper on memory allocation) and it should be almost 850MB of memory address space. When I had 4GB without 4G remapping the computer also showed the exact same avaible memory as with 3GB (around 2.3 GB).

Steelski,

The only reason I want the extra GB is that I use the computer for two things: games and photo/video editing. With photo/video editing the extra gig makes a difference. With games the extra gig does nothing and actually removing the 1GB might actualy help a little but with better memory timmings.

Papah
 

Steelski

Senior member
Feb 16, 2005
700
0
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Originally posted by: papaHesch
Peter,

I would usually agree but what could possibly be using almost 2GB of memory addresses? Why when I have only three sticks (2* 1GB sticks and a 512MB stick) does the system post 2.5 GB vs 2.3GB with 4 sticks. I have done the math with all the devices in my computer (got the space used from a technical white paper on memory allocation) and it should be almost 850MB of memory address space. When I had 4GB without 4G remapping the computer also showed the exact same avaible memory as with 3GB (around 2.3 GB).

Steelski,

The only reason I want the extra GB is that I use the computer for two things: games and photo/video editing. With photo/video editing the extra gig makes a difference. With games the extra gig does nothing and actually removing the 1GB might actualy help a little but with better memory timmings.

Papah

I photo edit happily on only 1 gig, i really could do with some more on that front.
I am at a loss with this problem.
I could suggest a X200 ATI motherboard because i have heard good things about the board when it comes to adressing 4 sticks. then again i dont know if that will fix the problem. As i said i photo edit at 1 gig. files that are usually 40-200mb each. but with video edeting. I am at a loss. you could edit with 2.5 gig. or you could get 1 stick of 1 gig ram and sell the 2x512 mb. have you contacted the ram manufacturers. they might be able to help if there is a known issue with that board or chip. unfortunatley as noone here has the exact config you have its very hard to speculate.