A8N-VM CSM with 4 DIMM

I could not get A8N-VM CSM motherboard to work with four PC3200 DIMM
modules (4 GB in total) - the memtest86+ was giving errors on all
tests. When tested individually, all modules are passing all memtest
tests. Also, up to two modules in dual channel mode are passing all
tests. I'm not overclocking.

Has anyone been able to get 4 GB to run in this or *any* 939
motherboard?

My config is:

ASUS A8N-VM CSM, rev 1.10G, BIOS ver 0702
Corsair Value Select memory, VS2GBKIT400C3 (2 kits, 4 identical DIMM
modules, 4 GB total). Timing 3-3-3-8
Processor AMD Athlon 64 X2 4400+ (2200 MHz)
memtest86+ version 1.65

Thanks.

Bitstring <. com>, from
the wonderful person said
>I could not get A8N-VM CSM motherboard to work with four PC3200 DIMM
>modules (4 GB in total) - the memtest86+ was giving errors on all
>tests. When tested individually, all modules are passing all memtest
>tests. Also, up to two modules in dual channel mode are passing all
>tests. I'm not overclocking.
>
>Has anyone been able to get 4 GB to run in this or *any* 939
>motherboard?

Yes, many people have done so by dropping back to 333Mhz instead of 400
Mhz. Of course you will not see all 4GB in WinXp, but you should still
see a lot more than 2GB.

--
GSV Three Minds in a Can
Google may be your friend, but groups.google.com posters definitely aren't.

GSV Three Minds in a Can wrote:
> Bitstring <. com>, from
> the wonderful person said
> >I could not get A8N-VM CSM motherboard to work with four PC3200 DIMM
> >modules (4 GB in total) - the memtest86+ was giving errors on all
> >tests. When tested individually, all modules are passing all memtest
> >tests. Also, up to two modules in dual channel mode are passing all
> >tests. I'm not overclocking.
> >
> >Has anyone been able to get 4 GB to run in this or *any* 939
> >motherboard?
>
> Yes, many people have done so by dropping back to 333Mhz instead of 400
> Mhz. Of course you will not see all 4GB in WinXp, but you should still
> see a lot more than 2GB.
>
> --
> GSV Three Minds in a Can
> Google may be your friend, but groups.google.com posters definitely aren't.

Perhaps I should have mentioned I have been running it at 333 MHz,
3-3-3-8, 2T. DRAM voltage cannot be adjusted on this motherboard ... it
runs at whatever voltage the A8N-VM CSM provides it.

Do you actually have 4 GB on your socket 939 board? What mobo is it?

Bitstring <. com>, from
the wonderful person said
>
>GSV Three Minds in a Can wrote:
>> Bitstring <. com>, from
>> the wonderful person said
>> >I could not get A8N-VM CSM motherboard to work with four PC3200 DIMM
>> >modules (4 GB in total) - the memtest86+ was giving errors on all
>> >tests. When tested individually, all modules are passing all memtest
>> >tests. Also, up to two modules in dual channel mode are passing all
>> >tests. I'm not overclocking.
>> >
>> >Has anyone been able to get 4 GB to run in this or *any* 939
>> >motherboard?
>>
>> Yes, many people have done so by dropping back to 333Mhz instead of 400
>> Mhz. Of course you will not see all 4GB in WinXp, but you should still
>> see a lot more than 2GB.
>>
<snip>

>Perhaps I should have mentioned I have been running it at 333 MHz,
>3-3-3-8, 2T. DRAM voltage cannot be adjusted on this motherboard ... it
>runs at whatever voltage the A8N-VM CSM provides it.
>
>Do you actually have 4 GB on your socket 939 board? What mobo is it?

Nope, I have no use for that much memory, but there are plenty of forums
that describe it (usually) working, yea, even with Asus motherboards
IIRC. Try backing off the timing some more, if that is an option?

--
GSV Three Minds in a Can
Google may be your friend, but groups.google.com posters definitely aren't.

In article <. com>,
wrote:

> I could not get A8N-VM CSM motherboard to work with four PC3200 DIMM
> modules (4 GB in total) - the memtest86+ was giving errors on all
> tests. When tested individually, all modules are passing all memtest
> tests. Also, up to two modules in dual channel mode are passing all
> tests. I'm not overclocking.
>
> Has anyone been able to get 4 GB to run in this or *any* 939
> motherboard?
>
> My config is:
>
> ASUS A8N-VM CSM, rev 1.10G, BIOS ver 0702
> Corsair Value Select memory, VS2GBKIT400C3 (2 kits, 4 identical DIMM
> modules, 4 GB total). Timing 3-3-3-8
> Processor AMD Athlon 64 X2 4400+ (2200 MHz)
> memtest86+ version 1.65
>
> Thanks.

The first thing to do:

Install two sticks of memory. Test with memtest86+ and do not
boot into Windows unless there are zero errors in two complete
passes of the test. Then, boot into Windows and get a copy of
CPUZ ( www.cpuid.com/cpuz.php ). Check your settings in CPUZ, to
make sure you are not pushing the components on your motherboard
past their ratings.

The normal CPU clock is 200MHz. The BIOS setup of the memory
controller assumes it is 200MHz. If you set the CPU to 250MHz,
for example, and set the memory target to DDR400, the actual speed
seen in CPUZ would be DDR500. So check first that the CPU can
drive the memory at nominal conditions of CPU=200MHz. The default
Auto settings in the BIOS should have set the CPU to 200MHz.

Loosely speaking, on the Athlon64 dual channel platform, stability
is affected by the memory speed setting, a thing called Command
Rate, and the Vdimm memory supply voltage. In the user manual for
your board, the latter two options don't appear to exist. One would
hope that the memory voltage is at least 2.6V, to run memory rated
at DDR400.

The possible combinations, from least memory bandwidth, to most
memory bandwidth:

DDR333 Command Rate 2T (most conservative)
DDR333 Command Rate 1T (max for four sticks in dual channel)
DDR400 Command Rate 2T (good for two sticks in dual channel, especially
if you plan to overclock the memory and the
memory is rated higher than PC3200)
DDR400 Command Rate 1T (may be possible to run two sticks at this
condition, depending on the processor)

If it was my memory, I would try to set the BIOS to the topmost
values above, when there are two sticks in the machine, shut down,
and install the other two sticks. Maybe the BIOS will use Command
Rate 2T by default - I cannot say what your BIOS might do.

There are tools for adjusting memory parameters while in Windows,
like A64tweaker, but the thing is, the board has to be error free,
before you should be booting Windows.

My conclusion would be, based on the current lack of settings in
the BIOS, that the A8N-VM CSM is not an enthusiast board, and
it lacks the essentials to work properly with Athlon64 processors.
This is one of the reasons that I recommend downloading and reading
the manual for these products, before you buy them. Now, maybe the
latest BIOS on the Asus site has added some settings, but I doubt it.

Asus policy on memory doesn't seem to be too consistent between
members of the Athlon64 motherboard family. For example:

For A8N-VM CSM, it says:
http://support.asus.com.tw/faq/faq_r...Language=en-us

"To ensure system stability, the BIOS has fixed the maximum
memory speed to*333MHz*according to AMD memory timing guidelines.
Therefore, manual adjustment*will have*no*effect."

On the A8N-SLI, it says:
http://support.asus.com.tw/faq/faq_r...Language=en-us

"To be more compatible and stable with some memory modules, the
default clock will be at 333MHz if four DDR400*memory modules*
are plugged on the A8N-SLI. But you still can set at 400MHz
manually in the Bios to gain better performance."

So, if you check with CPUZ and the memory is already running
DDR333 Command Rate 2T, when the four sticks are installed, that
is the best you can do. Maybe with a more fully featured BIOS,
you could tweak and tune the thing into submission. But based on
what I can see in the published user manual, it doesn't look like
you have enough options to do this in a safe conservative manner.

You might consider dropping the memory clock speed or the CPU
clock speed, long enough to boot error free into Windows, and then
use clockgen from cpuid.com and/or A64tweaker, and do your adjusting
that way. Maybe you'll get it set up right that way.

The Athlon64 is not as sensitive to memory bandwidth as the P4,
so reaching the almighty DDR400 Command Rate 1T is not an
imperative.

Paul

Paul, thanks for excellent suggestions. Unfortunatelly, I could not get
this board to pass the memtest86+ error free with 4 1GB sticks, not
even at 3-3-3-8, 2T, 333 MHz (btw those are also settings that the
memory vendor recommends). Each individual stick, and up to any
combination of 2 sticks are passing multiple passes of all tests
without a glitch. And yes, I had the most recent BIOS. Lowering the CPU
speed did not help either (although, even if it did, I would not be
willing to make that sacrifice). After all, ASUS is advertising this
board as being able to support Athlon64 X2 family AND 4 GB of RAM. I
understand this is not an "enthusiast" board ... but the basic
advertised functionality *should* work never the less. I returned the
board ...Asus did not even bother to respond to me. I'm still waiting
for the new board to arrive ... we'll see how that goes.