SB Overclocking Thread

[Axon]

What kind of PLL is everyone running? At 4.6 i'm running 1.4v. What the hell does PLL even do?

Yeah, 1.4 is low, realllly low. Stock is 1.8v, and while a number of people reporting that a small drop of PLL voltage increases stability, I haven't seen a 1.4v report...ever.

 

[jacktesterson]

With new MSI board, got 4.4 at 1.29v

After 4.4 I need to add a lot more juice to stabilize so not worth it to go any further
At this time.

 

[Juji]

Just built.my new system today with an 2600k, cause the 2500k was out of stock
I just turned up my multiplier to 40, and my h70 keeps the chip at 32 degress when im playing wow, is the h70 that good or is it the chip which dosent get hot?
Temp was measured on the asus utility, is that inaccurate?
Im gonna get coretemps when i get home, just to see if that shows the same.
Anyway, its a great cpu, i had a mobile p8400 earlier so its quite a difference

 

[Castiel]

Yeah, 1.4 is low, realllly low. Stock is 1.8v, and while a number of people reporting that a small drop of PLL voltage increases stability, I haven't seen a 1.4v report...ever.

Unfortunately i can't get 4.9ghz stable with the PLL that low. Going to have to up it if i want more. I can boot with 50X100 with 1.4 vcore and 1.4v pll but windows always freezes

 

[pm]

What kind of PLL is everyone running? At 4.6 i'm running 1.4v. What the hell does PLL even do?

The PLL is the Phase Locked Loop. It's an analog circuit inside the chip designed to take the external BCLK/refCLK signal from the motherboard clock generator and then generate internal clocks for the rest of the chip at all phase aligned to each other. The voltage for the PLL is often separated from the main power for the chip for noise-related reasons - so it gets it's own supply so that power events on the main CPU supply don't mess up the clock circuitry. As far as what various voltage adjustments would do, I don't know, but in general PLL's are carefully tuned for a specific voltage it's rare that changing that voltage would result in better results for that circuit. In particular the VCO (Voltage Controlled Oscillator) circuit tends to be sensisitive to supply changes. For more than you ever wanted to know about PLL's look at: http://www.sentex.net/~mec1995/gadgets/pll/pll.html

 

[Castiel]

The PLL is the Phase Locked Loop. It's an analog circuit inside the chip designed to take the external BCLK/refCLK signal from the motherboard clock generator and then generate internal clocks for the rest of the chip at all phase aligned to each other. The voltage for the PLL is often separated from the main power for the chip for noise-related reasons - so it gets it's own supply so that power events on the main CPU supply don't mess up the clock circuitry. As far as what various voltage adjustments would do, I don't know, but in general PLL's are carefully tuned for a specific voltage it's rare that changing that voltage would result in better results for that circuit. In particular the VCO (Voltage Controlled Oscillator) circuit tends to be sensisitive to supply changes. For more than you ever wanted to know about PLL's look at: http://www.sentex.net/~mec1995/gadgets/pll/pll.html

Thanks PM

 

[Dadofamunky]

Well done, PM.

Didn't pass Prime blend test overnight at 4.5 GHz 1.29V so I stepped up the CPU voltage to 1.325. All four cores stable for over an hour now.

When this procedure is done I may set the PLL back to Auto. I doubt Intel's PLL breaks the established practices. It's looking like this setup is about done. Except for the SSD and video card upgrades, which will come later.

 

[Seven]

Just turn that PPL off and set the cpu vcore to offset > auto. Works great for me though.

 

[Dangerer]

Very happy with my 2500k

4.4 Ghz at 1.26V (bios). CPU-z reports between 1.240-1.256.

24 hours stable with Prime95 small FFT, OCCT medium, OCCT large.

Hottest core is around 60c on load.

 

[Diogenes2]

Finally satisfied with my OC.. Took a little while to learn the ins and outs of the new BIOS ..

2600K Asus P8P67 Pro BIOS ver. 1053
Here are the relevant settings in the BIOS

AI Overclock Tuner = Manual
BCLK = 100
By All Cores ( Can Adjust in OS ) = 49
Load-line Calibration = High
CPU Offset Voltage = .135

Everthing else is pretty much default. I can check a specific item if anyone is interested.

Memory is 16GB Mushkin @ 1333. Cooler is CoolerMaster 212+

I will probably change to 4.8g because I can lower LLC to Medium. and vcore offset to .12; which ends up being about 1.38 max in CPUZ, while temps stay below 70..

 

[Draax]

I finally got my 2600k up to 5GHz stable, but temps do get a little hot. Tried at 5.2GHz and it posts but hangs on windows logo. The F6A bios is what allowed me to get to 4.8+ and higher as it allowed me to enable PLL over-volting.

Vcore=1.5v
CPU PLL=2.0v
PLL Overvolting=enabled
Load line calibration=enabeled
Ram=standard

 

[Guerrilladawg]

Finally satisfied with my OC.. Took a little while to learn the ins and outs of the new BIOS ..

-pic-

2600K Asus P8P67 Pro BIOS ver. 1053
Here are the relevant settings in the BIOS

AI Overclock Tuner = Manual
BCLK = 100
By All Cores ( Can Adjust in OS ) = 49
Load-line Calibration = High
CPU Offset Voltage = .135

Everthing else is pretty much default. I can check a specific item if anyone is interested.

Memory is 16GB Mushkin @ 1333. Cooler is CoolerMaster 212+

I will probably change to 4.8g because I can lower LLC to Medium. and vcore offset to .12; which ends up being about 1.38 max in CPUZ, while temps stay below 70..

So you got 4.9 Ghz with a 'budget cooler' while temps are only ~75C at Prime Max load? That's awesome tbh

I was thinking to get a H50 myself...would it get even better temps? Or is the 212+ just that awesome?

 

[SickBeast]

I finally got my 2600k up to 5GHz stable, but temps do get a little hot. Tried at 5.2GHz and it posts but hangs on windows logo. The F6A bios is what allowed me to get to 4.8+ and higher as it allowed me to enable PLL over-volting.

Vcore=1.5v
CPU PLL=2.0v
PLL Overvolting=enabled
Load line calibration=enabeled
Ram=standard

Isn't 1.5v way too much for a SB CPU? You're playing with fire, literally.

 

[Draax]

Isn't 1.5v way too much for a SB CPU? You're playing with fire, literally.

Intel White sheet says 1.52v. If you want to get 5GHz+ you are going to have to put that much through. When testing CPU-Z says its drawing about 1.48v. I would be more concerned with temps.

 

[Diogenes2]

So you got 4.9 Ghz with a 'budget cooler' while temps are only ~75C at Prime Max load? That's awesome tbh

I was thinking to get a H50 myself...would it get even better temps? Or is the 212+ just that awesome?

Don't know about the H50, or if lowering the temps would even be to my advantage at this point.
If you look at the interface on the 212, it's hard to tell the difference between it and a lot of coolers costing twice as much. With four heat pipes and a solid fit, I think it would be hard to do much better as far as air is concerned ... I'm using IC Diamond 7 Carat thermal paste. It seems to work really well also..

 

[Castiel]

I run an H70 on my 2600K and it performs great. If spending over 100 bucks on a cooler look at the RAsa kit on frozencpu

 

[RaistlinZ]

I finally got my 2600k up to 5GHz stable, but temps do get a little hot. Tried at 5.2GHz and it posts but hangs on windows logo. The F6A bios is what allowed me to get to 4.8+ and higher as it allowed me to enable PLL over-volting.

Vcore=1.5v
CPU PLL=2.0v
PLL Overvolting=enabled
Load line calibration=enabeled
Ram=standard

Congrats on 5GHz! :biggrin: What kind of cooler are you using?

 

[AdamK47]

If it's 100% stable at 5GHz with 1.5V for 24/7 use and you can keep temps within reason, go for it. I would.

 

[Dadofamunky]

Dayum... Intel really let the cat out of the bag here. 5 GHz OC? Geesh.

 

[Draax]

Congrats on 5GHz! :biggrin: What kind of cooler are you using?

I am using the Noctura D14. I switched out the 2 noctura fans for some of my more powerful scythe fans. Even so the temps at 5GHz are a little too hot, peaking at 84. I think I will run it at 4.8GHz 24/7 because I only need 1.45v and the temps never break 72-73 at that voltage. Here is a pick of 4.8GHz.

 

[Viper GTS]

Anybody happen to know where the disable HT option is hidden in Gigabyte's BIOS? I was looking into my low GFLOPs reading in IntelBurnTest & it seems HT may lower the score. I'd like to disable it just as a sanity check to make sure everything is as expected. I took a quick run through the BIOS & didn't see it, surely it must have the option right?

On a side note, I'm working on getting the timings tightened up on my memory. It is nowhere near stable with the rated timings at 1.5V (probably because I have 4 DIMMs). 1.58 V looks like it may be enough to fix that, is that a worthwhile tradeoff to make or should I just run it at 1.5V? I know Intel frowns on the higher memory voltages but lots of people seem to run high voltage memory with no real issues.

Viper GTS

 

[flopper]

5ghz using 1.4vcore idle and 1.44 load.
2500k.

best deal I had in ages with a computer.

 

[spawn447]

ive got my 2500k / asus pro @ 4.5 w/1.25 vcore in bios .
min temp 28c - max 58 using a TRUE with an antec tri fan @ medium speed(1600 rpm) .

question is :
cpu-z 1.56.3 shows it droop to 1.216v , asus ai suit sensor shows 1.2v and real temp 3.67 shows 1.3711 VID . so whats the right voltage

 

[T101]

Intel White sheet says 1.52v. If you want to get 5GHz+ you are going to have to put that much through. When testing CPU-Z says its drawing about 1.48v. I would be more concerned with temps.

This is a misconception that 1.52V is [k]safe[/k] because of the intel white sheet. It is just the maximum programmable voltage. On xtremesystems forum there is already users who have had their cpus degrade (2 days I think it took) running close to 1.5V. I would not exceed 1.35V and even that is just a hunch, not tried and tested to be "safe".

 

[Draax]

This is a misconception that 1.52V is [k]safe[/k] because of the intel white sheet. It is just the maximum programmable voltage. On xtremesystems forum there is already users who have had their cpus degrade (2 days I think it took) running close to 1.5V. I would not exceed 1.35V and even that is just a hunch, not tried and tested to be "safe".

If I didn't want to overclock I would not have purchased the 2600k. 1.35v is way too conservative. The nay-sayers were out in full force when I was putting 1.55-1.6 through my E6750, as well. That rig put up with that for years and is still running 24/7 in my basement.