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mem 3.5gig to 4 issue help... MB bad?

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I haved searched and read for hours now on this issue of mem reporting below the 4 gig that are on the board. I did the mimo hole thing and still get 3.5 gig reported on boot up and in windows x64. I have swapped each stick with a new one I got yesterday and it reports the same telling me its not a bad stick... what a fun $100 expeirment that was. I am recalling months ago that it use to report 4gig, maybe before i updated the bios in june. I've also noticed that if I disable the sli broadcast aperture setting I get 3.75 reported on boot up and in x64... why is this and do I need this option on? Is there another bios option holding the other .25 gig?

some memtest nums for you to help guide me are

ram 167 MHz (ddr334) / CAS : 2.5-3-3-7 / dual channel

Cashed 3583M RsvdMem 276M


also not looking to really over clock here just run right... for those that are going to ask why 4 gig (just run 2) well I render video and heavy on the multi-task :P

DRAM Configuration Settings:


DRAM Frequency Set - by DRAM SPD Value

Command Per Clock (CPC) - Disable

CAS Latency Control (Tcl) - Auto

RAS# to CAS# delay (Trcd) - Auto

Min RAS# active time (Tras) - Auto

Row precharge time (Trp) - Auto

Row Cycle time (Trc) - Auto

Row refresh cyc time (Trfc) - Auto

Row to Row delay (Trrd) - 02

Write recovery time (Twr) - 02

Write to Read delay (Twtr) - 02

Read to Write delay (Trwt) - 03

Refresh Period (Tref) - 3120

Write CAS Latency (Twcl) - enable

DRAM Bank Interleave - enabled


DQS Skew Control - auto

DQS Skew Value - 0

DRAM Drive Strength - auto

DRAM Data Drive Strength - auto

Max Async Latency - auto

DRAM Response Time - fast

Read Preamble Time - auto

IdleCycle Limit - 256

Dynamic Counter - disable

R/W Queue Bypass - 16 x

Bypass Max - 07 x

32 Byte Granularity - disable(4 Bursts)



any suggestions? and anyone know the waranty time on this board? I cant seem to find it in my paper mountain.

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ok flashed back to the 2006/03/29, shows on boot up 393...(goes by too fast for me to get whole number) and 3.75 gig in x64. however this is with the sli broadcast aperture disabled... again what/why is this setting? any more help please? should I try an older bios like from 11/2005?

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Okay... simply put, the motherboard ain't gonna let you.


I had 4GBs once and even with 4GBs in, it only told me I had around 3.5 or so in after I enabled the remapping because it uses 500MBs to make everything run smoother and such, then it showed up as 2.8 in Windows XP (non-64)


Be happy you've got it showing what you do, it's using that last bit for good things.


My booting when I had 4GBs (running at 400MHz) was faster than my booting with 2GBs at 500MHz.

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There are many that write better than myself and here is one of those instances as relates the 4gig Memory Limitations...


The problem that you are seeing is based on an older architecture design for memory addressing. All the systems architecture up to this point were based on a maximum of 4GB of total memory. Nobody really thought, when this standard was designed, that this amount of memory would actually be in use. The problem that has happened is that you have PCI devices that require memory address ranges so that they can properly execute their commands. These address ranges were mapped in the upper sections of this maximum amount. Since nobody thought you would be using up to 4GB these address ranges started around the last 500MB of the memory ranges. This range is called the T.O.M. or Top of Memory range. This is the point in the bios where it places on hold the amount of memory that is required by the various PCI devices that are found on the motherboard. Thus when you have PCI cards or AGP cards installed on your motherboard these devices hold on to memory for their own use and take away from the maximum amount of memory that is available for other tasks. This amount of memory can vary from a little as 200MB all the way to 1GB of memory (or even more in select cases). It just depends on the PCI devices you have and the amount of PCI (including AGP) that you have installed all at once.


There is really no way to get around this basic design limitation. The only way to get around these type of issues is to use certain new designs that have brand new architectures (i.e 64-bit designs) that allow memory to be mapped in area's above 4GB. The brand new Intel Xeon designs and the AMD Opteron designs are built around 64-bit technology. This is only ½ of the equation that you would need to find success. You would also need to use an OS that is actually PAE or PAE aware so that it is able to address memory above the 4GB level. To find out about PAE you can search Microsofts website for PAE (Physical Address Extensions) and it will explain this concept and what OS's actually are capable of providing this benefit. Windows 2000 and Windows 2003 would fit both of these criteria. Windows XP on the hand would not allow this type of ability.


And all current boards have PCi devices installed including but not limited to the onboard chips for sound and nic...well let me make that not so broad a statement because I can think of maybe one board in another manufacturers line-up that might not have any PCi devices but if even it supports any PATA devices it most likely will have at least some PCi devices onboard...to this date the PCi buss is not dead fully in any situation that I am aware of...



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well thanks all... for the schoolin. let me add though...ya maybe it said 4gig befor I added the 2nd vid and audio cards... wierd. thanks again.

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I imagine Vista will be designed to handle much more as it will likely be the basis for Microsofts server operating systems, which can use upwards of 32GB.


No promises, though of course you could check and see what people can do with the Beta or try it out yourself. If I ever get another 2 gigs I'll give Vista a shot again.

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heh... sorry deleted the vista question, probably while you were replying, because I found MS site that yes vista will do up to 32 gig.... yay :)

now what kinda MB has that many mem slots and where can i get one... lol.

also i'm still wondering about the mem test error... any clue what to do here? could the slot be bad? and what is that hex addy pointing too?

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