A8N-SLI using 2Gbytes memory modules?

  • Thread starter Thread starter Hp
  • Start date Start date
H

Hp

Hello,

does this board or AMD-CPU support already 2 GByte memory modules? To
go for 4/8 GBytes of system memory.

Hp
 
Hp said:
Hello,

does this board or AMD-CPU support already 2 GByte memory modules? To
go for 4/8 GBytes of system memory.

Hp
Click to expand...

I know that 4GB is the max for the board, so I also assume that 1GB per
module is the max (but not 100% sure). I am sure about the 4 GB total for
the board being the maximum.
 
Hello,

does this board or AMD-CPU support already 2 GByte memory modules? To
go for 4/8 GBytes of system memory.
Click to expand...

Nope, afaik-- since the board max is 4Gbyte.

Consult the user-manual. Download on-line at www.asus.com

John Lewis
 
Nope, afaik-- since the board max is 4Gbyte.
Consult the user-manual. Download on-line at www.asus.com

John Lewis
Click to expand...

AMD tells :

Several AMD Opteron processor-based motherboards currently support
some of the following memory features:

- PC1600, PC2100, PC2700, and PC3200 registered memory modules

- 184-pin 2.5-V and 2.6-V DDR DIMMs

- 28-bit DDR memory bus

- 64-Mbyte, 128-Mbyte, 256-Mbyte, 512-Mbyte, 1-Gbyte, 2-Gbyte and
4-Gbyte memory technology

- Production DIMMs from industry standard DRAM memory manufacturers.

- Only registeredtype memory modules should be used.


Cheers

Hp
 
Have just seen on the Athlon 64 FX Unbuffered DIMM AVL pdf file from
AMD June 2005:

Samsung M368L5623MTN-CB3 2G 128M * 8

Hp
 
John said:
Nope, afaik-- since the board max is 4Gbyte.

Consult the user-manual. Download on-line at www.asus.com
Click to expand...
It indeed lists 4GB as the maximum (as do most other socket 939 boards).
However, I'm not quite sure where this limitation comes from or if it
even exists in practice, apparently the cpus (which containg the memory
controller) support 4 x 2GB modules just fine, for instance the abit ul8
board is advertized to support 8GB ram.
So this only leaves board layout (1 address line not wired, seems
unlikely), chipset (the same chipset with a different name for the
workstation market supports it, and I'm not sure the chipset is involved
at all) or bios (obviously needs to support memory address remapping,
but it needs this already for the full use of 4GB).

Roland
 
Roland Scheidegger said:
It indeed lists 4GB as the maximum (as do most other socket 939 boards).
However, I'm not quite sure where this limitation comes from or if it
even exists in practice, apparently the cpus (which containg the memory
controller) support 4 x 2GB modules just fine, for instance the abit ul8
board is advertized to support 8GB ram.
So this only leaves board layout (1 address line not wired, seems
unlikely), chipset (the same chipset with a different name for the
workstation market supports it, and I'm not sure the chipset is involved
at all) or bios (obviously needs to support memory address remapping,
but it needs this already for the full use of 4GB).

Roland
Click to expand...

I find AMD to be very evasive on this issue. Only the 26094.pdf
"BIOS and Kernel Developer's Guide" discusses setup for various
sizes of DRAM modules, and I cannot find docs anywhere on the
AMD site that say what the total memory limits are.

BIOS 1006 on the Asus download page, lists "Add Memory Re-map function
SETUP Item", and BIOS 1007 says "Modify SETUP String and it's
discription of DRAM Over 4G remapping function". It sounds like
there is BIOS support for the memory hoisting function needed
to punch a hole below 4GB for I/O purposes.

The Samsung M368L5623MTN-CB3 is listed here:

"Validated DIMMs - AMD Athlon 64 Processor"
http://www.amd.com/us-en/Processors/DevelopWithAMD/0,,30_2252_893_10125,00.html
http://www.amd.com/us-en/assets/content_type/DownloadableAssets/Athlon_64_Unbuffered_DIMM_AVL.pdf

So all the ingredients are there, except the sure knowledge
that the Nvidia chipset doesn't have some issue with
interconnecting to a processor that has 8GB of memory.

Perhaps a call to Asus Tech Support will clear this up.
Sending Asus a copy of "Athlon_64_Unbuffered_DIMM_AVL.pdf"
might speed up the process :-)

Paul
 
It indeed lists 4GB as the maximum (as do most other socket 939 boards).
However, I'm not quite sure where this limitation comes from or if it
even exists in practice, apparently the cpus (which containg the memory
controller) support 4 x 2GB modules just fine, for instance the abit ul8
board is advertized to support 8GB ram.
Click to expand...

Load capacitance on the memory control lines -- potentially taking
timings out of spec.............. ??

Anyway, why the desire for 8Gbyte on a single-processor desktop
configuration ?

John Lewis
 
Load capacitance on the memory control lines -- potentially taking
timings out of spec.............. ??

Anyway, why the desire for 8Gbyte on a single-processor desktop
configuration ?

John Lewis
Click to expand...

The module listed here has speed rating B3 (DDR333)

http://www.samsung.com/Products/Sem.../UnbufferedDIMM/M368L5623MTN/M368L5623MTN.htm

On this component page:
http://www.samsung.com/Products/Semiconductor/common/product_list.aspx?family_cd=DRM030106

that would correspond to the unstacked K4H1G0838M 128Mx8 chip.

http://www.samsung.com/Products/Sem...0838M/ds_ddr_1gb_m_die_x4x8_pb_free_rev11.pdf

From page 10, Cin is 2-3 pF on address, 4-5pF on data.

For comparison, here is a 64Mx8 chip:

http://www.samsung.com/Products/Sem...8C/ds_ddr_512mb_c_die_tsop2_x4x8x16_rev11.pdf

It has the same input capacitance spec. Same even on a 32Mx8 chip.

So the chips should not prevent this from working.

(The stacked chips have exactly double the input capacitance,
so you don't want to be using those.)

Paul
 
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