MOBO Recomendations please

[SaturJames]

Hello! So if you read my other post you'd see that I'm up a
high-density creek. Can someone please tell me a make and model of a
mobo that'll support my new 1gb DDR400 PC3200 HIGH DENSITY (that's the
key, the high-density) stick of ram, please?

 

[Paul]

Hello! So if you read my other post you'd see that I'm up a
high-density creek. Can someone please tell me a make and model of a
mobo that'll support my new 1gb DDR400 PC3200 HIGH DENSITY (that's the
key, the high-density) stick of ram, please?

There is a list of chipsets for the bad 1GB module in the
right hand column.

http://www.portatech.com/catalog/memory.asp?ID=285

*** Verify that you have a motherboard with a
VIA PT800, KT600, P4X266A chipset or a
SIS 648, 648FX, 746FX chipset before purchase

I guess the KT600 would be a candidate. You can get
a list of boards supporting KT600 here. Asus has
three A7V600 boards in the list and there are
a total of 78 motherboards listed.

http://www.motherboards.org/mobot/index.html

I tried looking at the addressing modes needed for
128Mx4, and I cannot see why the addressing would be
a problem. But addressing usually shows symptoms of
only giving the user half the memory capacity, and
in your case, the beep pattern and failure to POST
means there is some more serious error being flagged
by the BIOS. It could be the translation to rows/cols/bank
simply isn't in the Northbridge logic and that is why
the BIOS has to crash out. But a KT600 doesn't have
a good reason to support the necessary address mode
either, so that is a real puzzler for me. The necessary
detail is not available for the KT600 - if there was
a datasheet for it, maybe then I could make sense of
it. Addressing 128Mx8 chips is different than 128Mx4,
and the modes are not the same, and I cannot see how
being able to use 128Mx8 chips, makes the mode available
for 128Mx4 chips. So I just don't get why the KT600
would be a candidate, unless perhaps it also supports
registered DIMMs. But I thought the KT333 had secret
support for registered as well... Its a puzzle, and
I'd rather have some proof the chipsets have a reason
to support the memory, rather than relying on the
Portatech advert.

So you gambled on the 128Mx4 chips on your module,
and now you'll be gambling that a KT600 will fix it.
Good luck.

I've already read somewhere, that Nforce2 doesn't
support 128Mx4, and only uses 64Mx8. You might look
on Nforcershq.com for evidence for or against that
statement, as I don't have a URL for that.

Paul

 

[hyc]

I tried looking at the addressing modes needed for
128Mx4, and I cannot see why the addressing would be
a problem. But addressing usually shows symptoms of
only giving the user half the memory capacity, and
in your case, the beep pattern and failure to POST
means there is some more serious error being flagged
by the BIOS. It could be the translation to rows/cols/bank
simply isn't in the Northbridge logic and that is why
the BIOS has to crash out.

It's not address lines, it's data strobes. DIMMs that use x4 DRAM chips
need twice as many data strobes as modules using x8 chips. Take a look
at one of the module data sheets for an example.

http://www.samsung.com/Products/Sem...M312L5623AUS/ds_ddr_1gb_a_die_rdimm_rev11.pdf
(pages 6-8 show the component schematics)

This is the main reason most registered DIMMs won't work on AMD Socket
939 systems - most registered DIMMs use x4 parts, and Socket 939 only
has enough data strobe lines for x8 or x16 parts. What's really
annoying is that companies like Samsung also made high capacity (2GB)
modules with x8 components, but they don't seem to be for sale
anywhere.

(If anyone knows where I can buy these M312L5623AUS-CCC (Samsung 2GB
DDR ECC/REG DIMM) please let me know, thanks.)