With proper cooling the Q6600 should run stable at 3.0GHz with no further moddings, but that will also depend on the stepping revision. The G0 can be easily overclocked with stock cooling. Don't bother if it's a B3.

I disagree with not bothering with the B3 stepping as I have one that is a great clocker (3.8 @ 1.55V). You will need good cooling if going over 3 GHz but even a B3 should do 3GHz without fancy cooling. If the Q6600 happen to be a G0 then 3 GHz is almost guarenteed at stock voltage and with luck you will get 3.2, with a fancy tower cooler 3.6 GHz @ ~1.5V is the realistic goal.

If you are using the computer for XP I would keep the E8400 but for any newer version of Windows I would choose the Q6600.

One thing to think about with the Q6600, if you are overclocking using more than 1.35V on an older motherboard you need to make sure your board has at least some air flow over the VRM mosfets as they get hot. If your motherboard is a newer X38/X48/P45 board this is less important as all boards with those chipsets have many power phases and/or heatsinks on the mosfets, airflow over the VRM mosfets is still a good idea though.

Skyscraper wrote:

I disagree with not bothering with the B3 stepping as I have one that is a great clocker (3.8 @ 1.55V). You will need good cooling if going over 3 GHz but even a B3 should do 3GHz without fancy cooling. If the Q6600 happen to be a G0 then 3 GHz is almost guarenteed at stock voltage and with luck you will get 3.2, with a fancy tower cooler 3.6 GHz @ ~1.5V is the realistic goal.

If you are using the computer for XP I would keep the E8400 but for any newer version of Windows I would choose the Q6600.

One thing to think about with the Q6600, if you are overclocking using more than 1.35V on an older motherboard you need to make sure your board has at least some air flow over the VRM mosfets as they get hot. If your board is X38/X48/P45 this is less important as all boards with those chipsets have many power phases and/or heatsinks on the mosfets, airflow over the VRM mosfets is still a good idea though.

1.55V seems really high to me

smeezekitty wrote:

Skyscraper wrote:

I disagree with not bothering with the B3 stepping as I have one that is a great clocker (3.8 @ 1.55V). You will need good cooling if going over 3 GHz but even a B3 should do 3GHz without fancy cooling. If the Q6600 happen to be a G0 then 3 GHz is almost guarenteed at stock voltage and with luck you will get 3.2, with a fancy tower cooler 3.6 GHz @ ~1.5V is the realistic goal.

If you are using the computer for XP I would keep the E8400 but for any newer version of Windows I would choose the Q6600.

One thing to think about with the Q6600, if you are overclocking using more than 1.35V on an older motherboard you need to make sure your board has at least some air flow over the VRM mosfets as they get hot. If your board is X38/X48/P45 this is less important as all boards with those chipsets have many power phases and/or heatsinks on the mosfets, airflow over the VRM mosfets is still a good idea though.

1.55V seems really high to me

Kentsfield can take 1.6, even more if kept reasonable cool. Its the board I would worry about if it dosnt have 6+ power phases or good VRM mosfet cooling. With that said 1.55V is a good safe limit. Anything over 1.35V - 1.4V isnt safe for motherboards with 3-4 powerphases and no air flow over the VRMs when overclocking a quad though.

I meant not to bother unless heavy modding is what he wants to do.

filipetolhuizen wrote:

I meant not to bother unless heavy modding is what he wants to do.

Perhaps he already has a tower cooler? and if not you can get a decent one for $30.

Changing cooler and if necessary adding a fan for some airflow over the motherboard is not what I would call heavy modding.

I'm running on Windows 7.
The Asus P5QL Pro uses the P43 chipset.

Based on some "guides" from other users who have overclocked their Q6600's to 3 GHz, they seem to be able to run their CPU stable at a vCore voltage of 1.2625V.
However, as mentioned before, I'm not looking at breaking any overclocking records. I'm just look at overclocking to 3 GHz and not higher than that.
Would the CPU then perform better than the E8400?

jesolo wrote:

I'm running on Windows 7. The Asus P5QL Pro uses the P43 chipset. […]
Show full quote

I'm running on Windows 7.
The Asus P5QL Pro uses the P43 chipset.

Based on some "guides" from other users who have overclocked their Q6600's to 3 GHz, they seem to be able to run their CPU stable at a vCore voltage of 1.2625V.
However, as mentioned before, I'm not looking at breaking an overclocking records. I'm just look at overclocking to 3 GHz and not higher than that.
Would the CPU then perform better than the E8400?

Yes if the E8400 isnt overclocked the Q6600 @3 Ghz will be faster in most tasks, especially in newer games. Both CPUs use a 9x multiplier so the FSB will be the same and you can run the memory at the same speed you do now.

At 3GHz cooling wont be a problem but your board only has 4 power phases and no VRM mosfet heatsinks so If you decide to overclock to a greater speed using alot more voltage then you need good air flow over the VRM area.

Skyscraper wrote:

jesolo wrote:

I'm running on Windows 7. The Asus P5QL Pro uses the P43 chipset. […]
Show full quote

I'm running on Windows 7.
The Asus P5QL Pro uses the P43 chipset.

Based on some "guides" from other users who have overclocked their Q6600's to 3 GHz, they seem to be able to run their CPU stable at a vCore voltage of 1.2625V.
However, as mentioned before, I'm not looking at breaking an overclocking records. I'm just look at overclocking to 3 GHz and not higher than that.
Would the CPU then perform better than the E8400?

Yes if the E8400 isnt overclocked the Q6600 @3 Ghz will be faster in most tasks, especially in newer games. Both CPUs use a 9x multiplier so the FSB will be the same and you can run the memory at the same speed you do now.

At 3GHz cooling wont be a problem but your board only has 4 power phases and no VRM mosfet heatsinks so If you decide to overclock to a greater speed using alot more voltage then you need good air flow over the VRM area.

Agreed, hence why I only want to overclock to 3 GHz and not higher than that. I checked, I have the G0 stepping (SLACR)
I have Corsair DDR2-800 RAM (4 x 1 GB) in my PC so, that shouldn't be a problem.
Any good benchmark tests you can recommend?

is it a B3 or a G0? if its a G0 you can up the voltage by .05 and set it to 400mhz FSB and hit a magical 3600mhz pretty easy

jesolo wrote:

Agreed, hence why I only want to overclock to 3 GHz and not higher than that. I checked, I have the G0 stepping (SLACR) I have […]
Show full quote

Skyscraper wrote:

jesolo wrote:

I'm running on Windows 7. The Asus P5QL Pro uses the P43 chipset. […]
Show full quote

I'm running on Windows 7.
The Asus P5QL Pro uses the P43 chipset.

Based on some "guides" from other users who have overclocked their Q6600's to 3 GHz, they seem to be able to run their CPU stable at a vCore voltage of 1.2625V.
However, as mentioned before, I'm not looking at breaking an overclocking records. I'm just look at overclocking to 3 GHz and not higher than that.
Would the CPU then perform better than the E8400?

Yes if the E8400 isnt overclocked the Q6600 @3 Ghz will be faster in most tasks, especially in newer games. Both CPUs use a 9x multiplier so the FSB will be the same and you can run the memory at the same speed you do now.

At 3GHz cooling wont be a problem but your board only has 4 power phases and no VRM mosfet heatsinks so If you decide to overclock to a greater speed using alot more voltage then you need good air flow over the VRM area.

Agreed, hence why I only want to overclock to 3 GHz and not higher than that. I checked, I have the G0 stepping (SLACR)
I have Corsair DDR2-800 RAM (4 x 1 GB) RAM in my PC so, that shouldn't be a problem.
Any good benchmark tests you can recommend?

Frybench and Cinebench are good benchmarks to test all cores.

3dmark 11 if your video card is a DX11 card. 3dmark Vantage if your video card is a older DX10 card.

candle_86 wrote:

is it a B3 or a G0? if its a G0 you can up the voltage by .05 and set it to 400mhz FSB and hit a magical 3600mhz pretty easy

G0 stepping (SLACR).

candle_86 wrote:

is it a B3 or a G0? if its a G0 you can up the voltage by .05 and set it to 400mhz FSB and hit a magical 3600mhz pretty easy

I have not seen a single Q6600 that would do 3600 with +0.05V if you do not do a vdrop/vdroop mod (or activate such a feature in BIOS if available)

My best Kentsfield needs ~1.35V load voltage to hit 3600 Prime x64 stable and that is a 4+ GHz capable QX6850.

+.05 is 1.35, the Q6600's normally run at 1.30V

Q6600 default voltage is more like 1.25V... 1.3 would be too much.
Also overclocking to 3.6 GHz is not that easy - mine will only go up to 3.3 GHz. 🙁 http://hwbot.org/submission/2372173_havli_cin … %29_3.63_points

candle_86 wrote:

+.05 is 1.35, the Q6600's normally run at 1.30V

Yes most Q6600 G0 has a VID of around 1.25V - 1.325V, the motherboard sets the (full speed) idle voltage to ~0.05V below that (all boards do this) and the load voltage will be somewhat lower than the idle voltage on newer boards, alot lower on some older boards.

To get a load voltage of 1.35V you need to set 1.4V+ often 1.45V+ in the BIOS or activate Vdrop/Vdroop elimination if the board has it.

havli wrote:

Q6600 default voltage is more like 1.25V... 1.3 would be too much.
Also overclocking to 3.6 GHz is not that easy - mine will only go up to 3.3 GHz. 🙁 http://hwbot.org/submission/2372173_havli_cin … %29_3.63_points

Eh?

The default voltage varies from chip to chip. Not all are created equal. 1.3 is definitely not too much either. Even 1.4V should be safe
My old E6700 used to run 3.0GHz with 100% stability at stock voltage (1.232V)

-edit-

I looked it up on Intel's site and amazingly they say even 1.50V is safe: http://ark.intel.com/products/29765/Intel-Cor … Hz-1066-MHz-FSB

havli wrote:

Q6600 default voltage is more like 1.25V... 1.3 would be too much.
Also overclocking to 3.6 GHz is not that easy - mine will only go up to 3.3 GHz. 🙁 http://hwbot.org/submission/2372173_havli_cin … %29_3.63_points

every Q6600 GO or B3 I've owned ran at 1.3V reported by CPUz and Aida64. And thats strange, every q6600 G0 I've ever seen has hit at least 3.6, ive had a few to 4

smeezekitty wrote:

Eh? […]
Show full quote

havli wrote:

Q6600 default voltage is more like 1.25V... 1.3 would be too much.
Also overclocking to 3.6 GHz is not that easy - mine will only go up to 3.3 GHz. 🙁 http://hwbot.org/submission/2372173_havli_cin … %29_3.63_points

Eh?

The default voltage varies from chip to chip. Not all are created equal. 1.3 is definitely not too much either. Even 1.4V should be safe
My old E6700 used to run 3.0GHz with 100% stability at stock voltage (1.232V)

Had a quick look - the Q6600 is rated to go up to 1.5V. However, the lower you can go, the less heat is being generated, less power is being consumed and you probably will extend the life span of the CPU.