Here's the history. I've had this motherboard for about 4 months now. Got it in early March.

I initially had a Pentium D 960 (3.6 GHz) running @ 4.0 ghz.

I recently bought an E6600 C2D and i have G.Skill DDR2800-PC26400 Ram with blue heatspreaders.

Problem: I Could OC the Pentium D to 4 ghz and higher on air cooking, but the E6600 Won't go past 2.6 GHz without bluescreens, errors, whatever.

BUT, for those of you wo have a P5W DH Deluxe or an Asus motherbaord that supports Overclocking profiles, I used some of the default ones, and i used the Overclocking profile of 20% which brought it up to 2.88 GHz and it seems to run fine ...only problem is, it brings my ram down to PC2-3200 instead of 6400.

I don't get it. Other than that, is there any other settings the overclocking profile could be using that i'm not aware of?

I've tried changing voltages, vcore all the way up to 1.475v no luck, I keep the ram as close to 800mhz as possible and it is a decent overclocker, because at 2.6 GHz, it's running at 864, or 889 mhz (don't quite remember), so the ram isn't the issue, i don't suspect.

I've read that the ram supports 1.8v-1.9v, is it cool to bring it up to 2.0 or even 2.2v? and as for the processor, should i up it even more from 1.475 to achieve the 2.88 the overclocking profile gives me? i'd use it if not for it bringing my ram down to pc2-3200.

Any suggestions?

Change the overclocking profile to "Manual".

Change the FSB to 333 and change the RAM speed to DDR2-667, leave everything else as stock.

I have the exact MB and CPU as you but Corsair DDR2-667 as my RAM, and I'm running at 3.0GHz without changing the voltage.

Radish™

When you say, set the ram speed to DDR2-667, do you mean 667MHz? Shouldn't freeza set his to 800 MHz since he has PC2-6400 memory which is 800 MHz?

I'm not really sure, but thought I'd ask.

Thanks for the suggestions Radish, but no dice.

Are any of your voltages changed from auto?

or any settings for that matter?

Seems the ONLY way i can push this thing past 2.6 is to use the overclocking 20% profile which brings my memory down to 3200... but the thing is, the memory right now is at 867 mhz with 2.6 ghz and it works fine. Right now the fsb is 289 mhz.

Changing it to 333 mhz makes vista x64 give errors about winload.exe being corrupt, oh and NTOSkrnl when i lowered it to 300 mhz instead of 333.

I know that but wanted to see if the PC would boot using underclocked RAM.

Radish™

None of my voltages are changed, they are all on "Auto".

Make sure you have the latest BIOS v2004. Under "JumperFree Configuration" the "AI Overclocking" is set to "Manual", the "FSB/CPU External Frequency Sync" is set to "333" and the "DRAM Frequency" is set to "DDR2-667".

That's all I've changed to get my E6600 to 3.0GHz. You may also need to set your memory timings manually, which is given by the manufacturer of the RAM.

Radish™

how weird. everything is set like that too.

Memory timings are set manually. this sucks!

Radish, do you have speedstep turned off?

What are your options for the CPU section?

the PCI-E bus, and all that?

you should try leaving the ram timings on spd, and turning off hyperpath, and speedstep, then see if you can overclock manually, in my experience it seems to overclocka lot better with hyperpath off and ram timings on spd.

I have the same MB and was wondering how to set the memory timings manually. I've looked through the manual and all through the bios. Where do you go to do this? Thanks

RADISH! SUCCESS.

I changed the ide type from ahci + all that power saving crap to just regular ahci and turned the pci-e from faster peg link to auto and a lowered it to ddr-667 and set the timings 5-5-15-5 or something like that and it works!!!!!!

BUT I STILL NEED TO KNOW IF YOU HAVE SPEEDSTEP ON.

i disabled every single processor feature and i have no idea if that's why it's working or not.

but i liked having speedstep, disable bit, and a bunch of the other processor features turned on.

so if you can report back if you have those enabled or not i can try them.

I have no use for Speedstep, so it's off. I use NX Bit and Intel VT for my virtual machines.

Glad to see you got it working, now since you have DDR2-6400 - you should no problems upping the FSB higher than 333 (providing you update the Vcore).

Just make sure that when you update the FSB, the RAM speed changes accordingly but leave it at DDR2-800 to allow a 1:1 ratio.

Radish™

I have it working with the DDR2-667 method.

Thanks a lot Radish.

One more question:

Is it worth the decrease in memory speed to get a 600 mhz overclock?

That's why I said before as you have DDR2-800, you can overclock even more as your RAM has more speed to give. So where you typed in "333" for the FSB, change it to a higher number e.g. "400" and you will see the RAM speed correspond to match the FSB you have chosen but even though the MB has chosen it you can change it to match your RAM.

You need to make the FSB match the DDR2-800 speed for a nice decent overclock with a 1:1 ratio.

Radish™