ô_ô wrote:
The key to the board, may be in a BIOS setting. Apparently dual channel is not
the setting you want. The chipset may have a stability problem, or the problem
is the quality of BIOS code provided by SIS to the motherboard makers.

http://www.abxzone.com/forums/memory...hlight=p4s800d

In the BIOS, I see:

"Advanced Hyperstreaming Engine"

Well, that item is an optimization for a number of
different I/O or memory access behaviors. The BIOS
defaults to [Disabled], but maybe changing it would
help. I'd leave changing this setting, until you've
exhausted the other possibilities.

http://www.sis.com/hyperstreaming/tech_02-01.htm

For "Performance Mode", [Auto] is the default, and
you could try [Normal] and see if that makes a difference.

For "DRAM Timing", [Auto] is the default, and that should
be reading the timings from the SPD on the DIMM. You are
getting 3-4-4-8 and that is probably the value stored in
the DIMM. Again, [Normal] is another option, but I cannot
see any other source of info other than the SPD EEPROM on
the DIMM. In the case of both these settings, the two
options are illogical, but in the world of BIOS designers,
you still have to try both of them, and see what happens.

"128 bit access mode" defaults to [Auto]. The options are
128*1 (dual channel) versus 64*2 (presumably single channel).
The Abxzone thread suggests the 64*2 is more stable, but
may erode performance a bit.

"CH0 MA 1T/2T Select" -- Command rate setting channel 0
"CH1 MA 1T/2T Select" -- Command rate setting channel 1

Normally, a setting of 1T for each, would be appropriate
with only two sticks installed (like in slot 1 and slot 3).
The 2T (slower) option should be used if you install four
sticks. The Abxzone thread is recommending [2T] for better
stability.

You can use memtest86+ from memtest.org to test the memory.
Memtest86+ had a bandwidth indicator (the third readout down
on the left of the screen). This is an example of what the
memtest86+ screen looks like, and this motherboard has a
memory bandwidth of 2393MB/sec. (Which would be normal for
an 865PE at stock settings and dual channel mode.)

http://www.pctuning.cz/ilustrace/cha...screen_big.jpg

I have a different motherboard than you, but I'll give you
a few more bandwidth numbers, to compare to your motherboard.

If I had a single stick of RAM installed:

3-3-3-8 timing (close to your timings) - 1584MB/sec
2-2-2-6 timing (my stick is faster than yours) - 1681MB/sec

In that case, the memory runs at DDR400 and has a
theoretical bandwidth of 3200MB/sec (PC3200). Due to the
efficiency of the memory bus, I only get the above
numbers. Those numbers would be "normal".

Now, if I install two sticks and run in dual channel mode:

2-2-2-6 timing (my stick is faster than yours) - 2732MB/sec

Also, if I install four sticks, I still get exactly 2732MB/sec,
and that will be a different behavior than your motherboard.

In the case of dual channel, I should be seeing a theoretical
value of 6400MB/sec total, yet 2732MB/sec is the best I can
do at stock settings (DDR400). The bus efficiency is about
42.7%. The memtest86+ access pattern for the bandwidth test
is purely sequential.

So, download memtest86+ and test your motherboard. Try the
"64*2" mode, which should be single channel, and try the
"128*1" mode. See what bandwidth figures are returned when
you boot memtest86+ floppy or CD version. Only boot back
into Windows, if the memory appears to be stable, and is
not throwing out errors on the memtest86+ screen.

The Asus forum is here, but I don't see any adverse comments
about your board. I know there were some issues with one
of the P4S series, where it didn't work properly with four
sticks, but that should not be affecting you right now.

http://vip.asus.com/forum/topic.aspx...Language=en-us

Paul

ô_ô wrote:
So how did you fix it ?

A future P4s800d user, might appreciate your wisdom.

Paul