Advice sought by overclocking newbie

Hello all,

My system comprises of the following:

Asus P5B mainboard (latest 1202 bios)
Intel E4300 CPU with Zalman CNPS7700-CN superflower heatsink & fan
2x 1Gb Patriot 6300 667 Low latency DDR2 memory (in dual channel config)
Heavy duty 550W PSU

From what I've been reading this "SHOULD" be capable of 3Ghz quite
easily,but this damn rig just keels over at anything over 2.4Ghz.

I've disabled all extra CPU features in bios, disabled spread spectrum,
enabled the clock multiplier adjust, and set the PCI and PCI-E at 33 and 100
respecively. All voltages are at auto (although I have tried upping the CPU
Vcore to 1.35v with no improvement).

Whenever I set the FSB at 300 or 333 it results in no beeps and no post -
even with the clock multiplier as low as 6 (lowest it will go). It will
happily run it all day at 266 * 9 with both core temperatures around 49
degrees under load (using the Intel TAT).

Any suggestions appreciated.

CaptainMAD wrote:
> Whenever I set the FSB at 300 or 333 it results in no beeps
> and no post - even with the clock multiplier as low as 6 (lowest
> it will go). It will happily run it all day at 266 * 9 with both core
> temperatures around 49 degrees under load (using the Intel TAT).
>
> Any suggestions appreciated.

My guess is that your "Dram Frequency" is either on Auto or has
been set for the speed of your memory, DDR2-667. This results
in asynchronous operation, so that when the "CPU Frequency" is
raised beyond a certain point, the memory is then forced out of
spec. Since your processor is spec'd to run at 800Mhz FSB, I
believe you should manually set "Dram Frequency" on 400 to give
you the 1:1 ratio. Then, at a CPU frequency of 333 Mhz, your
memory will be exactly at spec.