avatar1983

I have had my Q6600 for some time now, and I have had a stable overclock at 3.2Ghz on my XFX 780i (with vdroop pencil mod). My settings are 400x8 for this, and it is rock solid. 24h Prime95, memetest, all no problem. However, I have found it impossible to get to 3.6 with 400x9, regardless of what I do to the CPU voltages. My board voltages (i.e. CPU FSB, Nforce SPP, Nforce MCP, HT Nforce SPP) are as recommended by robilar here. Since this is stable at 400x8, I don't think I need to play with these for 400x9. Vcore is 1.41 for stable 3.2Ghz. I have even tried raising my vcore to 1.5, which is the highest I'm willing to go for safety, and even that does not make 400x9 stable. It will boot, and be fine for light tasks, but gaming will usually cause a crash to desktop, and prime95 will usually result in either a complete freeze or a reboot after about 1 hour, rather then just a failure. My impression is that most Q6600 are able to do 3.6Ghz quite happily at these voltage. Thermally I'm fine, I have a TRUE lapped with 2x 2000RPM Scythe Ultra Kaze fans. On 3.6Ghz prime95 usually tops out at about 59-62°C.

My question is, are there any other settings I can investigate for stability? What about for example GTLRef? Or is the consensus that I have a relatively poor overclocking chip? If so, would it be a good investment to by a Q9550 at some point?

Edit: VID of this chip is 1.2500 according to Coretemp 0.99.4.
Thanks for any help!

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losttsol

What is the VID of that chip? What speed are you running your RAM at when you try for 3.6GHz? Also, when you say 1.5v for vcore, is that what CPU-Z says it is under load or just your BIOS? You can take that chip higher than 1.5v. Generally 1.55v is considered more of the ceiling, but some people here go even higher, just depends if you can cool it well enough.

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shoot2scre

Can you post all your pertinent BIOS settings?

Sometimes boards can have "holes" where 400x9 won't boot but 399x9 or 401x9 will.


I would suggest smaller steps initially. Try getting from 3.2ghz up to 3.6ghz on a multiplier of 8 first maybe... before just jumping to a multi of 9 and a .4ghz speed increase...

Betrivent

It's the motherboard that has the FSB holes.. not the cpu :P

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shoot2scre

/Fixed

lol

heathmcabee

The number of Q6600's coming out today aren't that great of overclocker, as you stated. Most of the 1.3250 VID today have a hard time getting even 3.4 without 1.5v+. You can push 1.5 with your cooling and get it to around 3.4, but it is going to be a long shot that you reach 3.6 since your are already running 3.2 with 1.41volts stable. I could only reach 3.4 with my the highest VID with a whopping 1.52VCORE, and I bought this chip in May of 2008.

As for the Q9550, I think it would be a great investment. You will be able to hit 4.0GHZ with no where near the amount you are going to pump into that Q6600.

Show4Pro

Yeah, I think you have a newer chip. The ones with 1.3250VID. My Q6600 has 1.2250VID, and I test my OC at 3.4GHz solid 4hr Prime95 test with only 1.2750vcore. So its probably your chip, not the board.

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Q6600 @ 4.2Ghz

avatar1983

Well, with regards to the questions about motherboard holes, I'm not changing any setting on the board except for the CPU multiplier, so its 400x8 for stable 3.2Ghz, and 400x9 for unstable 3.6Ghz. So that should not have an impact. I've actually had this CPU for about a year.

My ram is OCZ SLI Ready 4-4-4-15 T2 800Mhz 2.1V 4x1 GB kit, and I run it at stock speeds at the moment. FSB:RAM ratio is 1:1 for the rated 800Mhz DDR. Latencies and Voltage are at rated values. None of this changes when I try the higher multiplier, and it's completely stable at the lower one.

Will post the VID as soon as I'm at the relevant machine. I seem to recall something like 1.275 or so... Will check and post.

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shoot2scre

Yes... I understood all that.

What I was saying is that jumping from a x8 to a x9 multiplier is a pretty unorthodox way of overclocking a chip.

Try x8 and 410... 420... 430... so on and so forth until you find your limits. Don't worry about your ram. You should be able to still run at something close to 444-15. You might have to loosen up timings a little... but it should work just fine.

Let me know if you have any luck going in smaller steps.

avatar1983

I got pretty distracted by work for a while, but now I have time to experiment with this some more.

The VID of this chip is 1.2500 as reported by Coretemp 0.99.4

That means it should probably be able to do a fair bit more then 3.2 @ 1.41Vcore, doesn't it? I realise VID is not an absolute indicator of OC potential, but it's a pretty good guideline.

I will see about overclocking in smaller steps this weekend and report.

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