I've been having an issue getting my Q6600 up to 3.0 ghz stable. I've been poking around this forum, and the internet for a few days, but the best I've achieved so far is that it won't *immediately* shut down. It does shut down after my mobo splash screen comes up, however.  
 
My system specs
 
Q6600 w/ Arctic Cooling Freezer 7 Pro
Gigabyte GA-P35-DS3L mobo
eVGA Nvidia 8800 GTS
2x2gb G.Skill DDR2 1066
 
I'm not completely new to overclocking, but this is my first time trying on a Core 2 machine. I've tried upping the cpu voltage, and then increasing the FSB slowly and incrementally, but it doesn't seem to work. Ram timings are set properly at 5-5-5-15, and as best I can tell there isn't anything that should be preventing it from working.
 
Anyone with any experience overclocking on a similar setup, I could really use some suggestions.

1st see:  
GUIDE: Overclocking On P35-DS3L
 

I have this mobo, and my quad is overclocked to 3.2 gigs heres how i did it. In the bios, set the voltages to auto, and then kick up your muliplier, save and start. I run totally stable going this route. You only want to mess with your voltages if your having problems with v-droop and such, but you should be able to get 3.0 gigs or higher by going this way.

^He is having RAM problems not FSB limitations or voltage, imo.

http://www.tomshardware.com/forum/ [...] oblem-help

You can't raise the multiplier on this chip. 9 is the max. you can lower it, but that's all.
 
This is probably some kind of memory divider issue.  hit CTRL+F1 in the main BIOS screen, that unlocks memory options.  set the fsb to memory ratio to 1:1, that will underclock the ram and allow headroom for oc.  Set the latencies to 5-5-5-15 manually.   Now you can raise the FSB to overclock the CPU.  3.0 shouldn't require any voltage increase.  
 
once you settle on a good CPU overclock, you may go back and begin messing with the memory bandwidth and latency timings.  

Your thinking of the wrong multiplier, im talking about changing it from 9x266 to 9x333.

Your thinking of the wrong multiplier, im talking about changing it from 9x266 to 9x333.

Going from 266 to 333 is changing the FSB, not the multiplier.

Ahh, well im confuseded then, but hey, worked for me.

After screwing around with it a bit more, I think it must be the ram. Tried 1:1, no boot. Even tried underclocking the stuff down to 667, no dice.
 
I'll probably just return the ram and pick up some DDR2 800, unless anyone has any more good suggestions.
 
Thanks, by the way, to everyone who has tried to help so far.

Dude i had the similar problem reaching 3. gigs with a g31 motherboard but i managed to do it ...fisrt u have to set the multiplier to 9 and the the FSB speed at 312 that gives u 2.808 GHz for now ... obviously reduce the time ram to 266 ... PCi-express 100 mhz...increase the voltage upto 1.48 and then in Vista and only in Windows Vista u have to use the EasyTune Utility provided in ur instalation Disc from Gigabyte ( Easy Tune 5.0 Pro if i remenber well) .... then use Cpu-z and u will see the voltage is running under voltage at 1.44 but stable...
 
Then execute Ntune at increase in little amonts the Fsb speed ( Overclocking Tab - Easy Mode ) first upto 2900 and then upto 333 * 9 = 2997 ...
 
Wait and dont run any program in the background neither open anything...
 
This program just works in Vista no Xp ....
 
I hope hs works 4 u
 
Sinceresly
Matador

Ah, I'm running XP 64, not Vista.

Umm, yeah. xp 64 is about as bad as millenium edition in my humble opinion.

^Many people run XP x64, esp. ppl who work with CAD,etc. I agree there are driver issues and such but If you do your research right you can avoid driver problems and the like with XP x64.

NEVER OC THROUGH WINDOWS It's just asking for trouble.

@OP: Just try some DDR2 667/800.

 
Yeah, it's not stellar, but 32 bit XP won't recognize all 4gigs of my ram.

Yeah, i just took the half a gig hit, and keep on truckin, but i guess im one of the few people whos o.s. actually recognizes most of the ram i have installed. And i totally agree with shadow, never oc through windows, plus gig sent a crap software to use for this purpose anyways, but stay away from it.
Incase your wondering both xp and vista with my system recognize 3.5 gigs, and with the hella low prices of ram these days, i decided i could live with half a gig being gone.

I have an EP35-DS3P, Q6600 cooled by a TRU120E, and 2 GB of Crucial RAM in an Antec 900 case running at 3.6 GHz. Prime95 runs 24 hours. Core temps go to 65C.
 
Getting started, I pretty much followed the P35 OC Guide.
 
Final settings were 9 X 400, System Memory Mult X2  
DDR2 Over volt: + 0.4 (Crucial specs 2.2 volts)
MCH  +0.100 volts
CPU voltage 1.45 volts (droops to 1.40 volts)
 
Pretty much the same settings for 3.3 GHz except
MCH +0.05 volts
CPU voltage  1.30 volts.
 
Prime95 kept failing at 8 to 12 hours before I bumped up the MCH voltage.
 
At 3.0 GHz, I did not need any CPU voltage increase.
 

I'm running a q6600 on a p35ds3l also.  Here's my settings if it helps.
(the VID on my cpu is 1.35 btw)
 
for 3.6 ghz:
400x9
Vcore=1.5v (droops to 1.46 idle, 1.425 loaded)
+.1v on FSB
+.1v on MCH
+.1v on RAM (running 2gb pc6400) timing@ 4-4-4-12
3.6 runs fairly stable for me, and temps at ~65 loaded with arctic freezer 7. It will fail on OCCT before an hour, but will run Prime95 for at least 8 hours for me.  
note: i did lap the HSF and CPU
Also, I put a small fan on the NB because it was getting very hot.  This solved the problem.
 
@3.4ghz
378x9
Vcore=1.425v
Ram +.1v
all other voltages at default.
This is what I run at 24/7.  Haven't gone past 8 hours on prime95, but is plenty stable.
 
@3.2
9x356 or 8x400
Vcore= 1.375v  
RAM +.1v
all other voltages stock (unless running 8x400, then FSB and MCH +.1v)
Running 8X400 gives a little better memory performance I think, but I also had to add voltage to FSB and MCH.  Though I installed NB fans, I'm still leery of overheating them.
 
On all of the overclocks I'm running the Ram 1:1 (2.0 on the ram multiplier in the BIOS).  And the RAM i'm using is 2gb of some low cost super talent stuff.  Seems to run well though at 4-4-4-12 with .1v overvoltage.   The temps I get with the Q6600@3.4ghz are ~35 ilde and ~60 loaded.  The temps were much higher however before I lapped the cpu and HSF.
 
I've booted and run 3dmark05 with the CPU@ 3.8ghz, but It required a Vcore over 1.6v.  Not to mention even more voltage to the FSB and MCH.  I just wanted to see if I could do it though...obviously wouldn't think of running those settings for any length of time.  
 
Obviously the Freezer Pro 7 isn't the best cooling option.  I'm debating whether to install a water cooler in this rig, or to buy a non **** case that will fit a 120mm air cooler.  

The two above posters are probably running DDR2 800 so they are able to OC. This shows that the motherboard is capable of being OCed.