How to overclock an Intel E8400 on an ABIT IP35Pro ?

Phil Weldon

'Erich Seidenschmiedt' wrote:
> hi Augustus, thanks for your hints. I have now tried to go even further,
> but anything beyond 432MHz seems to cause memory problems. However, I
> have so far not done any voltage changes except slightly raising the VCore
> to 1.295. Could any other voltage changes help to overcome the memory
> problem to some extent? I don't want to fool around a lot with voltages,
> since I am not sure whether I would ruin some of my hardware. So I'd
> appreciate very much any hints from experienced people. BTW, my RAM is:
> Corsair DHX DDR2 2x2048MB PC2-800, CL5
_____

How do you know the memory is causing problems? If you have a 2:1 (or 1:2
as some motherboard manuals will describe it) CPU Clock : Memory Clock
ratio, then DDR2-800 (also called PC6400; [800 X 4 X 2] ), then with the CPU
clock set at 432 MHz (FrontSide Bus speed of 1728 MHz) your memory is
running at DDR2-864 ( PC6900 speed equivalent). In this case your memory is
slightly overclocked (less than 10 %). Good quality memory should overclock
by more than 10 % with any memory voltage increases.

** The Orthos stress test has options to use 5 different sets of stress
routines; the first, small FFTs (fast Fourier transforms) takes place almost
entirely within the L2 cache, so memory is not stressed very much. The
large FFTs or the Blend option will stress memory because the data sets are
too large to fit in the L2 cache. You might try the two tests and check for
different behavior.

** Or you could try setting a CPU Clock : Memory Clock ratio that keeps the
memory clock low enough so that DDR2-800 speeds are not exceeded.

** Or you could relax the memory timings (which usually helps get higher
speeds (change the 5-5-5-9 timings that are probably the specified settings
for your memory to 9-9-9-15 and check the operation of the system.

At least one, perhaps all, of the suggestions above should show if the
memory is causing you to top out with a 1728 FSB speed.

As an example, I have 2 X 1 GBytes of DDR2-1066 (PC8500) memory that I run
at 1200 MHz (DDR2-1200, PC9600) using the same voltage as for operation at
DDR2-1066 speeds. {This memory is over a year old, and in March of 2007
DDR2-1066 memory required quite a bit higher than normal voltage to get that
speed, but some manufacturers certified the memory for 2.1 volts or higher
to get the rated speeds.} This in a nVidia 680i chipset motherboard (about
the fastest Intel Core 2 motherboard available back in March of 2007) with
an E4300 running with a FSB of 1200 MHz, a 50 % overclock with a CPU core
voltage about 10 % BELOW normal. The memory, a 1200 MHz, is clocked twice a
fast as is normal, but it gives slightly better performance at that speed
with relaxed timings than at the more usual speed (for a system using a 1200
MHz FSB) of 600 MHz; one of the advantages in overclocking a CPU with a
lower FSB speed B^)

Check your CPU temperatures using the Orthos stress test to make sure that
the CPU is not misbehaving at higher speeds because of being too hot.

Finally, you may notice a difference in terminology that posters in this
overclocking group use. That is because motherboard manuals from different
manufacturers use different terminology. In addition, many of the manuals
seem to be written in one language, translated to a second for corrections,
translated to a third for checking, then translated to a number of fourth
languages for distributions. Example, and least from reading the English
versions, using the word multiply when the desired meaning should be divide.

You already have a good overclock, so sit back and enjoy it as you slowly
work your way through the forest. There are probably thirty or more
parameters you can change in your BIOS the affect overclocking. You will
never need most of them (a good thing too, most of them do not have ANY
explanation in the manual).

Phil Weldon


"Erich Seidenschmiedt" <> wrote in message
news:12174$4831c95f$5471814c$.. .
> hi Augustus, thanks for your hints. I have now tried to go even further,
> but anything beyond 432MHz seems to cause memory problems. However, I
> have so far not done any voltage changes except slightly raising the VCore
> to 1.295. Could any other voltage changes help to overcome the memory
> problem to some extent? I don't want to fool around a lot with voltages,
> since I am not sure whether I would ruin some of my hardware. So I'd
> appreciate very much any hints from experienced people. BTW, my RAM is:
> Corsair DHX DDR2 2x2048MB PC2-800, CL5
> Regards, Erich