HOWTO: Overclock C2Q (Quads) and C2D (Duals) - A Guide v1.1

Upon further tests, I just couldn't keep stable at 3.5, and trying to get 3.3 for some reason wouldn't allow posting (***?) so I just went back down to 3.2, which is still powerful enough for me until I get water cooling.

Just updated the guide to version 1.3 which contains new info, fixes, clean-ups, etc. Enjoy!

Minor updates made.

Version is now 1.5.2 (updates in first post)

Guide is now version 1.6

• Added a detailed section to help you find the minimum stable CPU and MB vcore settings. Check it out (near the bottom of the guide entitled, “Stress Testing and Minimizing Your Vcores”)!
• Updated the CPU table
• Provided a less than $5 method you can use to shave off some NB load temps (in the thermal management section at the end of the guide).

Quote:

---

Originally Posted by graysky

@nater - your temps are very good for an air cooled machine... must be lapped?

---

No, actually it wasn't. I figured I just had a pretty good IHS...until I lapped it last week. The thing was seriously uneven. My Tuniq was lapped, but I don't see what difference that could make if the heat spreader itself is bumpy. The final result with air cooling was 3.51GHz @ 1.3975v. I could get it to POST and boot Windows at 3.6GHz, but I couldn't make it completely stable. Maybe with more vcore...but that's what the water setup is for.

I'm about done with the water cooling loop. It's taking forever because I'm using a lot of parts that you don't find in online PC retailers.

Version 1.6.1 is up. Totally re-wrote the section on memory which now includes a discussion on both DDR2/DDR3 and formulas you can use to calculate max supported FSB of a given module based on it's DDRX-Y and PCX-Y designations. Also re-ordered the first part of the guide.

nice write up!!

but I still have some question about the DRAM freq. my spec:
ASUS P5K-E wifi-AP
Intel Core2 Quad 2.40GHz Q6600
Patriot DDR2 800MHz 2GBx2 5-5-5-12 2T

for what i understand with my 800MHz ram I can overclock my CPU it to 400MHz = 3.6GHz right

But i dont understand the FSB:DRAM ratio part. according to CPU-Z my stock setting are Bus speed 267.3MHz, DRAM 400MHz, and ratio is 2:3. Is that mean in my BIOS CPU Freq is 267.3MHz and DRAM freq is DDR2-800MHz? What if i want to set the ratio to 1:1, in my BIOS CPU Freq is 267.3MHz and DRAM freq is DDR2-534.5MHz? what would my DRAM be for 1:1 ratio if my CPU Freq is 333MHz, 355MHz, 377MHz, and 400MHz?
What i dont understand is what is this ratio for? lower the ratio is less stable, and mean more heat to the ram?

just a few scattered thoughts on one of the recent comments: lapping
lapping's good if the heatsink is pretty warped or rough (though most shouldn't be... never got one that bad myself)

but that aside, deviations of less than a mm should be accomodated pretty readily by thermal compound. that's what it's there to do: bridge the gaps between the heatsink and your processor if you've gotta plaster it on though, best to lap. :)

Quote:

---

Originally Posted by chai

nice write up!!

but I still have some question about the DRAM freq. my spec:
ASUS P5K-E wifi-AP
Intel Core2 Quad 2.40GHz Q6600
Patriot DDR2 800MHz 2GBx2 5-5-5-12 2T

for what i understand with my 800MHz ram I can overclock my CPU it to 400MHz = 3.6GHz right

But i dont understand the FSB:DRAM ratio part. according to CPU-Z my stock setting are Bus speed 267.3MHz, DRAM 400MHz, and ratio is 2:3. Is that mean in my BIOS CPU Freq is 267.3MHz and DRAM freq is DDR2-800MHz? What if i want to set the ratio to 1:1, in my BIOS CPU Freq is 267.3MHz and DRAM freq is DDR2-534.5MHz? what would my DRAM be for 1:1 ratio if my CPU Freq is 333MHz, 355MHz, 377MHz, and 400MHz?
What i dont understand is what is this ratio for? lower the ratio is less stable, and mean more heat to the ram?

---

You might want to do some more research before you try and OC. But I'll cover some basics.

Bus speed = 266 = 133x2
DRAM speed = 400 = 133x3
Since it's DDR2 DRAM 400MHz x 2 (effective = the DDR2-800 rating)
Thus the 2:3 ratio.

If you want to go with a 1:1 ratio, you need your bus speed at 400. This will make your CPU bus be 400MHz, it will make your ram base clock be 400MHz (the 1:1 ratio). Then you are running your ram at stock clock speeds, and you don't incur any of the additional latency that arises from running non-matched clocks between the RAM and the FSB.

The hardest part about all this is that your ratio settings are tied to those bus speeds you have to select from. I would seriously suggest reading the Anandtech.com article about it to get a better idea of what you want to do.

Quote:

---

Originally Posted by James

You might want to do some more research before you try and OC. But I'll cover some basics.

Bus speed = 266 = 133x2
DRAM speed = 400 = 133x3
Since it's DDR2 DRAM 400MHz x 2 (effective = the DDR2-800 rating)
Thus the 2:3 ratio.

If you want to go with a 1:1 ratio, you need your bus speed at 400. This will make your CPU bus be 400MHz, it will make your ram base clock be 400MHz (the 1:1 ratio). Then you are running your ram at stock clock speeds, and you don't incur any of the additional latency that arises from running non-matched clocks between the RAM and the FSB.

The hardest part about all this is that your ratio settings are tied to those bus speeds you have to select from. I would seriously suggest reading the Anandtech.com article about it to get a better idea of what you want to do.

---

Thank
i been reading how to overclock all day long now. i'm deciding weather i should buy coolermaster V8 or V10 to cool my CPU. right now it running very hot even with the stock setting:

Prime 95 Test Time(min) 60 min
Room Temp (C) 24
Core 0 (Idle/Load) 59/92
Core 1 (Idle/Load) 57/90
Core 2 (Idle/Load) 52/83
Core 3 (Idle/Load) 55/81

Then overclock my q6600 to 3GHz (333*9) and then maybe to 3.2GHz (400*8)

FYI, bios version I'm using for my mobo is 2205 which is a beta version, hell, as long as it works, I ain't gonna care!