Question about DDR2

Hi All (though there doesn't seem to be too many posters to this group
anymore).

I have a cheap ECS RC410L motherboard and a Pentium D 805. This combo
will run 3.5Ghz overclocked...but for some reason its not perfectly
stable...it will
boot and run Prime 95 (two instances) fine for hours...but when I stop the
instances
of Prime 95 it crashes. It will run for hours and then all of a sudden I
get a BSOD.
I'm guessing this is somewhat a heat problem. I'm using stock cooling which
isn't that great.


I am also guessing that its a memory problem.

The memory it uses is DDR2-667...which should be able to run stable using a
FSB
of 166MHz or abouts? Its seems that this motherboard overclocked is stable
at 166FSB
but not very much higher.

Am I correct in believing that this DDR2 is only rated to FSB166 Mhz? Or
can it be
run higher? I tried a DDR2-800 stick of RAM in this mobo but it wouldn't
even boot.
Presumably this mobo doesn't take DDR2-800...but isn't that what would be
needed
to run the system reliably at 200FSB? That would be needed to run these
Pentium D 805s
at 4Ghz if possible? And would an enhanced CAS timing module help me
achieve a higher reliable
FSB. I'm confused a little bit...any help would be appreciated.

On Sun, 25 Jun 2006 07:33:32 GMT, "Don W. McCollough"
<letters RemoveThis @softhome.net> wrote:

>Hi All (though there doesn't seem to be too many posters to this group
>anymore).
>
> I have a cheap ECS RC410L motherboard and a Pentium D 805. This combo
>will run 3.5Ghz overclocked...but for some reason its not perfectly
>stable...it will
>boot and run Prime 95 (two instances) fine for hours...but when I stop the
>instances
>of Prime 95 it crashes. It will run for hours and then all of a sudden I
>get a BSOD.
>I'm guessing this is somewhat a heat problem. I'm using stock cooling which
>isn't that great.
>
>
>I am also guessing that its a memory problem.
>
>The memory it uses is DDR2-667...which should be able to run stable using a
>FSB
>of 166MHz or abouts? Its seems that this motherboard overclocked is stable
>at 166FSB
>but not very much higher.
>
>Am I correct in believing that this DDR2 is only rated to FSB166 Mhz? Or
>can it be
>run higher? I tried a DDR2-800 stick of RAM in this mobo but it wouldn't
>even boot.
>Presumably this mobo doesn't take DDR2-800...but isn't that what would be
>needed
>to run the system reliably at 200FSB? That would be needed to run these
>Pentium D 805s
>at 4Ghz if possible? And would an enhanced CAS timing module help me
>achieve a higher reliable
>FSB. I'm confused a little bit...any help would be appreciated.
>

I have the same motherboard and cpu, purchased at Fry's a few weeks
ago. I purchased a relatively inexpensive HSF (CoolerMaster) from
Newegg for $15, and mine is running stable at 20 x 166 mhz
(approximately 3.3 ghz). I have successfully run Prime95 (two
instances) for one hour at 20 x 175 (3.5 ghz), but I am running at 3.3
ghz as I prefer the lower temperatures. For some reason, cpuz will
not tell you the memory speed on this motherboard. However, judging
from the memory throughput numbers shown by memtest, the memory is
locked to the default value and does not change as you increase the
FSB from 133 all the way to 175.

My motherboard is not stable with two sticks of memory, I have tried
two different pairs of PC2-5300 memory (2 x 512). All four sticks are
stable when run individually, but not when run as pairs. I gave up
and purchased a single 1 gig stick of memory to use in the
motherboard.

Using the retail Intel HSF, I was hitting 72 degrees centigrade under
full cpu load at 20 x 150 (3 ghz). With the CoolerMaster, at 3.3 ghz
under full load, I am running about 65 degrees centigrade.

The built in ATI graphics seem fairly good (I am not a gamer), and
overall I am well pleased with this combo for the price. ($149 when I
purchased a few weeks ago, $129 in the latest Fry's ads).