DDR333 vs DDR400

my mobo requires a low density module i.e unbuffered of any type
(PC3200,PC2700).

i looked up my mobo on kingston's website and according do them, i
should buy this
http://www.valueram.com/datasheets/KVR333X64C25_1G.pdf

this is a DDR333 PC3200. I can't find this any cheaper than £55 ex.
del.

I can however find another kingston ram for much cheaper which is not
listed on their website along the rest of the ones compatible with my
mobo. however, looking at the datasheet for both, i cant see why it's
not compatible. everything is the same except that it's a DDR400 and
requires 2.6v power supply instead of 2.5v. as far as the DDR400 is
concerned, my mobo manual specifically says it supports it. as far as
the voltage is concerned, im sure drawing 0.01V more won't be a
problem. this is the one.
http://www.valueram.com/datasheets/KHX3200A_1g.pdf


I can get this delivered for £47 from saverstore. can i go for this
one? does the voltage matter?

/mobo: ASUS A7N8X

> "becktonglobe" <> wrote in message
> news: ups.com...
> my mobo requires a low density module i.e unbuffered of any type
> (PC3200,PC2700).
>
> i looked up my mobo on kingston's website and according do them, i
> should buy this
> http://www.valueram.com/datasheets/KVR333X64C25_1G.pdf
>
> this is a DDR333 PC3200. I can't find this any cheaper than £55 ex.
> del.
>
> I can however find another kingston ram for much cheaper which is not
> listed on their website along the rest of the ones compatible with my
> mobo. however, looking at the datasheet for both, i cant see why it's
> not compatible. everything is the same except that it's a DDR400 and
> requires 2.6v power supply instead of 2.5v. as far as the DDR400 is
> concerned, my mobo manual specifically says it supports it. as far as
> the voltage is concerned, im sure drawing 0.01V more won't be a
> problem. this is the one.
> http://www.valueram.com/datasheets/KHX3200A_1g.pdf
0.1v, not 0.01v...

> I can get this delivered for £47 from saverstore. can i go for this
> one? does the voltage matter?
The key is the line at the bottom of the page, if you select the A7N8X in
the Kingston search. It says:
"Although this motherboard specifies DDR400 compatibility, Kingston only
supports it with DDR266 and DDR333"

They are deliberately avoiding selecting any memory that is DDR400,
because the board sometimes gives problems at this faster rate. You can
use the DDR400 memory, but may find it is unreliable, unless you manually
set the memory tmings to the DDR333 rate.
When the guide was setup for this board, DDR333, was cheaper than DDR400.
Hence it made sense to play safe, and get the slightly slower memory,
which the automatic SPD settings worked for. It is purely that now the
market for faster memory has grown so quickly, that DDR400, is now
sometimes cheaper than DDR333, and you get the 'silly' result you are
seeing....

Best Wishes

On Apr 9, 9:42 pm, "Roger Hamlett"
<rogerspamigno...@ttelmah.demon.co.uk> wrote:
> > "becktonglobe" <becktongl...@googlemail.com> wrote in message
> >news: oups.com...
> > my mobo requires a low density module i.e unbuffered of any type
> > (PC3200,PC2700).
>
> > i looked up my mobo on kingston's website and according do them, i
> > should buy this
> >http://www.valueram.com/datasheets/KVR333X64C25_1G.pdf
>
> > this is a DDR333 PC3200. I can't find this any cheaper than £55 ex.
> > del.
>
> > I can however find another kingston ram for much cheaper which is not
> > listed on their website along the rest of the ones compatible with my
> > mobo. however, looking at the datasheet for both, i cant see why it's
> > not compatible. everything is the same except that it's a DDR400 and
> > requires 2.6v power supply instead of 2.5v. as far as the DDR400 is
> > concerned, my mobo manual specifically says it supports it. as far as
> > the voltage is concerned, im sure drawing 0.01V more won't be a
> > problem. this is the one.
> >http://www.valueram.com/datasheets/KHX3200A_1g.pdf
>
> 0.1v, not 0.01v...
>
> > I can get this delivered for £47 from saverstore. can i go for this
> > one? does the voltage matter?
>
> The key is the line at the bottom of the page, if you select the A7N8X in
> the Kingston search. It says:
> "Although this motherboard specifies DDR400 compatibility, Kingston only
> supports it with DDR266 and DDR333"
>
> They are deliberately avoiding selecting any memory that is DDR400,
> because the board sometimes gives problems at this faster rate. You can
> use the DDR400 memory, but may find it is unreliable, unless you manually
> set the memory tmings to the DDR333 rate.
> When the guide was setup for this board, DDR333, was cheaper than DDR400.
> Hence it made sense to play safe, and get the slightly slower memory,
> which the automatic SPD settings worked for. It is purely that now the
> market for faster memory has grown so quickly, that DDR400, is now
> sometimes cheaper than DDR333, and you get the 'silly' result you are
> seeing....
>
> Best Wishes

cheers. just installed the KHX3200A/1G and works fine. i have another
question however.

what changes do I need to make in the BIOS or elsewhere to get the
optimal performance out of this combination of RAM?

or am I just better off removing the old 256MB modules and just
running my new 1GB?