All We Know About Maximizing CPU Related Performance

[PunkNugget]

Hi Tutor,

I have read all the posts from every link you've provided 3 to 4 hours a day for the last 8 days straight and have tried every single type of BIOS adjustment possible to get my SR-2 (X5690 CPUs) above 156/101/13, but can't seem to break through that wall. I initially tried your post #70 here:

http://www.insanelymac.com/forum/index.php?showtopic=233891&st=60

...as well as all your other posts and PMs that you've sent me, but to no avail. So I went back to your Post #70 settings (below), and tried a few adjustments, but my system never completely started up and froze with all kinds of programming text that said - "panic(cpu 12 caller 0xffffff80002cf17f)... and so on..." & "Debugger called: <panic> Backtrace (CPU 12).". Now that CPU 12 issue was done on your settings (below). It even did that when I tried a slightly higher setting from 156/101/13 to 157/102/13 and this time it gave me "CPU 16" issues, instead of "CPU 12" issues.

Here are your underclocking results for your 24-7 settings:

1. No changes in Signal Tweaks yet.

2. No changes in Memory Configuration yet.

3. Frequency/Voltage Control

Both CPU's - Without VDroop

CPU 0 Vcore boot - 1.2750
CPU 1 Vcore boot - 1.2675
CPU 0 Vcore eventual - 1.3000
CPU 1 Vcore eventual - 1.2875

CPU VTT both boot - 1.325
CPU VTT both eventual - 1.350

CPU 0 DIMM Vcore - 1.65
CPU 1 DIMM Vcore - 1.66
IOH 1.35

Everything else at default or auto for now.

4. Frequency/Voltage Control
No Dummy O.C.
Target CPU - 2.17
CPU Freq. - 167
PCIE Freq. - 103
CPU Multi - 13
QPI - 4.8
Memory Freq. - 1066

Everything else at default or auto for now.

5. CPU Configuration

Everything is Enabled and/or set to Auto, including the newly exposed C1E, except MaxCPUID which is disabled.

Now your turbo boosting "pay day" is DDDDEE (and your X5680's).
_________________________________________________________________________

Now here's MY setup and the MAX that I'm (so far) able to push it to here:

1. No changes in Signal Tweaks yet.

2. No changes in Memory Configuration yet.

Initially I left it alone at it's BIOS system default from 7-7-7-20. But it froze and then changed it to actual memory latency of: 9-11-9-27 and also changed the command rate from 2 to command rate 1.

3. Frequency/Voltage Control

Both CPU's - Without VDroop

CPU 0 Vcore boot - 1.33125
CPU 1 Vcore boot - 1.33750
CPU 0 Vcore eventual - 1.33750
CPU 1 Vcore eventual - 1.34375
(I know you mentioned that I should go above 1.35V on my Vcore as to not fry my CPUs, and as you can see I haven't, but am I to go lower or make an exception and push them higher to 1.35 or even 1.375 as I have a slightly better CPU?)

CPU VTT both boot - AUTO (but it's default is 1.350V)
CPU VTT both eventual - AUTO (but it's default is 1.350V)

CPU 0 DIMM Vcore - 1.65
CPU 1 DIMM Vcore - 1.66
IOH 1.35

Everything else at default or auto for now.

4. Frequency/Voltage Control
No Dummy O.C.
Target CPU - 2.036
CPU Freq. - 156
PCIE Freq. - 101
CPU Multi - 13
QPI - 5.866GT
Memory Freq. - 1333
(I only changed the QPI and Memory Frequency because I have 2000MHz RAM and took your past advice by inputing these last two settings)

Everything else at default or auto for now.

5. CPU Configuration

Everything is Enabled and/or set to Auto, including the newly exposed C1E, except MaxCPUID which is disabled.

My turbo boosting "pay day" is EEEEFF (with my X5690s). Now I don't really know the difference between DDDDEE & EEEEFF, but I'm assuming because my X5690's are a bit different from your X5680's, this is why they're showing a slightly different letter change. Again, any help you can provide (or anyone else that may understand what I could be doing wrong), I am open to any input. I would love to get above a GB score of 33,200 and reach to a GB of 37,000+ running stable without lockups. Thanks...

 

[braindeadfool]

Hi Tutor,

I have read all the posts from every link you've provided 3 to 4 hours a day for the last 8 days straight and have tried every single type of BIOS adjustment possible to get my SR-2 (X5690 CPUs) above 156/101/13, but can't seem to break through that wall. I initially tried your post #70 here:

http://www.insanelymac.com/forum/index.php?showtopic=233891&st=60

...as well as all your other posts and PMs that you've sent me, but to no avail. So I went back to your Post #70 settings (below), and tried a few adjustments, but my system never completely started up and froze with all kinds of programming text that said - "panic(cpu 12 caller 0xffffff80002cf17f)... and so on..." & "Debugger called: <panic> Backtrace (CPU 12).". Now that CPU 12 issue was done on your settings (below). It even did that when I tried a slightly higher setting from 156/101/13 to 157/102/13 and this time it gave me "CPU 16" issues, instead of "CPU 12" issues.

Here are your underclocking results for your 24-7 settings:

1. No changes in Signal Tweaks yet.

2. No changes in Memory Configuration yet.

3. Frequency/Voltage Control

Both CPU's - Without VDroop

CPU 0 Vcore boot - 1.2750
CPU 1 Vcore boot - 1.2675
CPU 0 Vcore eventual - 1.3000
CPU 1 Vcore eventual - 1.2875

CPU VTT both boot - 1.325
CPU VTT both eventual - 1.350

CPU 0 DIMM Vcore - 1.65
CPU 1 DIMM Vcore - 1.66
IOH 1.35

Everything else at default or auto for now.

4. Frequency/Voltage Control
No Dummy O.C.
Target CPU - 2.17
CPU Freq. - 167
PCIE Freq. - 103
CPU Multi - 13
QPI - 4.8
Memory Freq. - 1066

Everything else at default or auto for now.

5. CPU Configuration

Everything is Enabled and/or set to Auto, including the newly exposed C1E, except MaxCPUID which is disabled.

Now your turbo boosting "pay day" is DDDDEE (and your X5680's).
_________________________________________________________________________

Now here's MY setup and the MAX that I'm (so far) able to push it to here:

1. No changes in Signal Tweaks yet.

2. No changes in Memory Configuration yet.

Initially I left it alone at it's BIOS system default from 7-7-7-20. But it froze and then changed it to actual memory latency of: 9-11-9-27 and also changed the command rate from 2 to command rate 1.

3. Frequency/Voltage Control

Both CPU's - Without VDroop

CPU 0 Vcore boot - 1.33125
CPU 1 Vcore boot - 1.33750
CPU 0 Vcore eventual - 1.33750
CPU 1 Vcore eventual - 1.34375
(I know you mentioned that I should go above 1.35V on my Vcore as to not fry my CPUs, and as you can see I haven't, but am I to go lower or make an exception and push them higher to 1.35 or even 1.375 as I have a slightly better CPU?)

CPU VTT both boot - AUTO (but it's default is 1.350V)
CPU VTT both eventual - AUTO (but it's default is 1.350V)

CPU 0 DIMM Vcore - 1.65
CPU 1 DIMM Vcore - 1.66
IOH 1.35

Everything else at default or auto for now.

4. Frequency/Voltage Control
No Dummy O.C.
Target CPU - 2.036
CPU Freq. - 156
PCIE Freq. - 101
CPU Multi - 13
QPI - 5.866GT
Memory Freq. - 1333
(I only changed the QPI and Memory Frequency because I have 2000MHz RAM and took your past advice by inputing these last two settings)

Everything else at default or auto for now.

5. CPU Configuration

Everything is Enabled and/or set to Auto, including the newly exposed C1E, except MaxCPUID which is disabled.

My turbo boosting "pay day" is EEEEFF (with my X5690s). Now I don't really know the difference between DDDDEE & EEEEFF, but I'm assuming because my X5690's are a bit different from your X5680's, this is why they're showing a slightly different letter change. Again, any help you can provide (or anyone else that may understand what I could be doing wrong), I am open to any input. I would love to get above a GB score of 33,200 and reach to a GB of 37,000+ running stable without lockups. Thanks...

I'm guessing CPU Vcore probably needs to be higher based on the panic codes you are getting. I would fix the CPU VTT values at 1.35 for the 5690s, but if you have more RAM than I you might need to squeak it up a notch--but only one notch. You also might try dropping the QPI frequency down to the next notch, as well. I personally would recommend that you insure stability testing in Windows, as the BSOD (Blue Screen of Death) does give you quite useful information with respect to overclocking, although it is very much processor family dependent. I also would recommend the "isolate" BCLK method of finding the BCLK value that you can reach

P.S. I know you want me to downgrade to 10.6.7....but I'm sort of married to 10.8 now. Especially since I've sold my GTX 580s and have GTX 680s.....

 

[PunkNugget]

I'm guessing CPU Vcore probably needs to be higher based on the panic codes you are getting. I would fix the CPU VTT values at 1.35 for the 5690s, but if you have more RAM than I you might need to squeak it up a notch--but only one notch. You also might try dropping the QPI frequency down to the next notch, as well. I personally would recommend that you insure stability testing in Windows, as the BSOD (Blue Screen of Death) does give you quite useful information with respect to overclocking, although it is very much processor family dependent.

Please forgive my ignorance, so as to not confuse anything that you're saying could you use this model (below) and make the adjustments you said so I can try them out and see if what you input could possibly work?

Frequency/Voltage Control
CPU 0 Vcore boot - 1.33125
CPU 1 Vcore boot - 1.33750
CPU 0 Vcore eventual - 1.33750
CPU 1 Vcore eventual - 1.34375

CPU VTT both boot - AUTO (at 1.350V) - So I should TYPE in: 1.35V - not leave on "AUTO" correct?
CPU VTT both eventual - AUTO (at 1.350V) - also TYPE in: 1.35V - not leave on "AUTO" correct?

CPU 0 DIMM Vcore - 1.65
CPU 1 DIMM Vcore - 1.66
IOH 1.35

Frequency/Voltage Control (main screen)
No Dummy O.C.
Target CPU - 2.036
CPU Freq. - 156
PCIE Freq. - 101
CPU Multi - 13
QPI - 5.866GT
Memory Freq. - 1333

In the meantime will buy a copy of Windows 7 and install it and try it there and use Prime95; if that's what I should use, correct? Or should I use a different Torture Testing program? The Prime95 (the newest one) for Mac doesn't really do anything except make CPU 1's RAM run hotter than usual and I have high heat sinks. I stopped after 5 min of use on that torture test as I don't think it's allocating the test properly.

I also would recommend the "isolate" BCLK method of finding the BCLK value that you can reach

Again, forgive my ignorance, but what do you mean by this comment?

P.S. I know you want me to downgrade to 10.6.7....but I'm sort of married to 10.8 now. Especially since I've sold my GTX 580s and have GTX 680s.....

No worries mate you have a great system and it gets great rendering scores and is a powerhouse as well, I just thought you wanted to cool down your office/room space and also push your system even beyond what Tutor is pushing us to do beyond his 40,100 GB score. I know it can get there, it's just knowing which to "notch up" and which to "notch down" in the BIOS.

BTW, I've never used Windows enough to get a BSOD. I can tell you that I do see a bunch of text and numbers when my system locks up in OS X. Does that text reveal anything or would the BSOD in Window reveal more details?

 

[Tutor]

Set all signal tweaks, except pcie ones, to max negative values; always give CPU 0 the higher values rather than CPU 1, and set boot VVT to 1.375 and set its eventual value to 1.4 and set IOH to 1.4.

 

[PunkNugget]

Set all signal tweaks, except pcie ones, to max negative values; always give CPU 0 the higher values rather than CPU 1, and set boot VVT to 1.375 and set its eventual value to 1.4 and set IOH to 1.4.

Okay, I've inputed the info you just said and so far I'm able to get up to 160/103/13 with a GB score of 34074. My CB score was 42.67/21.75. I rebooted to up it to 160/130/13 and then it a reset CMOS thing on me. From what my current BIOS is set to now, should I go up on my Vcore or down a notch on each one? Also, I know you mentioned that I should NOT go above 1.35V on my Vcore as to not fry my CPUs, but I have X5690s. Does that still apply or can I go a bit higher? Or am I supposed to go a bit lower?

Current BIOS Settings:

CPU 0 Vcore boot - 1.33750V
CPU 1 Vcore boot - 1.33125V
CPU 0 Vcore eventual - 1.34375V
CPU 1 Vcore eventual - 1.33750V

CPU VTT both boot - 1.375V
CPU VTT both eventual - 1.40V

CPU 0 DIMM Vcore - 1.65
CPU 1 DIMM Vcore - 1.66
IOH 1.40

Everything else at default or auto for now.

4. Frequency/Voltage Control
No Dummy O.C.
Target CPU - 2.080
CPU Freq. - 160
PCIE Freq. - 103
CPU Multi - 13
QPI - 5.866GT
Memory Freq. - 1333

I set all the Signal Tweaks (ST's) to ALL neg and left the PCIE ones on AUTO. I know that you mentioned that I should put (from Post #83) the ST's to this:

PCIe - Auto (both CPUs)
Max positive values for: IOH, CPU to CPU (both directions), all CPU DDR
Max negative values for: both CPU Impedance and both QPIs

but I didn't do that, as that's not what you instructed me to do this time around. Should I do it the other way around or not? Thanks...

 

[DJenkins]

I'm also hoping to get my head around all this one day soon!
Are there any quirks I should be aware of with the x5679 processors?
I have read they were oem HP server models... they've proven to be a bit tricky with which ram they like already.

At the moment just running mild 3.6GHz OC (noctua DH14 air cooling) and getting GB scores 28,000+ using dummy OC feature. I guess this is ok?

Also I know underclocking will maximize render performance as demonstrated... but will running at the lower clock speed have any disadvantage to regular applications or general use?

Use of this machine will be 50% after effects, 40% Cinema 4D, 10% photoshop, illustrator etc.

 

[Tutor]

... .I have read they were oem HP server models... they've proven to be a bit tricky with which ram they like already. Are there any quirks I should be aware of with the x5679 processors?

I have insufficient experience/info about x5679 [ http://www.cpu-world.com/CPUs/Xeon/Intel-Xeon X5679 - AT80614006924AA.html to guide you on their suitability for general use or a use of 50% AfterEffects, 40% Cinema 4D, 10% photoshop, illustrator etc.

At the moment just running mild 3.6GHz OC (noctua DH14 air cooling) and getting GB scores 28,000+ using dummy OC feature. I guess this is ok?

Quite good.

Also I know underclocking will maximize render performance as demonstrated... but will running at the lower clock speed have any disadvantage to regular applications or general use?

I have not experienced any downsides whatsoever in any app. over the last two years.

 

[Tutor]

Okay, I've inputed the info you just said and so far I'm able to get up to 160/103/13 with a GB score of 34074. My CB score was 42.67/21.75. I rebooted to up it to 160/130/13 and then it a reset CMOS thing on me. From what my current BIOS is set to now, should I go up on my Vcore or down a notch on each one? Also, I know you mentioned that I should NOT go above 1.35V on my Vcore as to not fry my CPUs, but I have X5690s. Does that still apply or can I go a bit higher? Or am I supposed to go a bit lower?

What I said is the higher that you go above Spec VID (1.35Vcore), the more likely you are to fry the CPU or scramble your storage medium, etc. Where that point of no return is - is anyone's guess, but for you it'll have negative consequences. So you can go higher at your own risk, but I don't advocate it unless you are willing to suffer the consequencies.

... . I know that you mentioned that I should put (from Post #83) the ST's to this:

PCIe - Auto (both CPUs)
Max positive values for: IOH, CPU to CPU (both directions), all CPU DDR
Max negative values for: both CPU Impedance and both QPIs

but I didn't do that, as that's not what you instructed me to do this time around. Should I do it the other way around or not? Thanks...

You can give it a try.
You are at the stage now where YOU have to find the true potential of those particular CPUs and your other system components. You must increase your knowledge of each of your system's components and how they interact and to experiment to go much higher.

 

[Tutor]

Continuing to put the finishing touches on some Sandy Bridge 6 [ http://www.cpu-world.com/CPUs/Core_i7/Intel-Core i7-3930K.html ], 16 [ http://www.cpu-world.com/CPUs/Xeon/Intel-Xeon E5-2680.html ] and 32 core ( [ http://www.cpu-world.com/CPUs/Xeon/Intel-Xeon E5-4650 - CM8062107184516 (BX80621E54650).html ] Pic w/o expansion chassis) systems for faster media production. These 4 particular 8-core 4650s base freg. is 2.7 GHz, but they turbo up to 3.5 GHz just like the 2680s. Benches are a few weeks off. So I'll continue to be in seeming hibernation, leaving voyagerd, Echrei, braindeadfool, PunkNugget and SR2Mac in charge of the class.

 

[braindeadfool]

Please forgive my ignorance, so as to not confuse anything that you're saying could you use this model (below) and make the adjustments you said so I can try them out and see if what you input could possibly work?

Frequency/Voltage Control
CPU 0 Vcore boot - 1.33125
CPU 1 Vcore boot - 1.33750
CPU 0 Vcore eventual - 1.33750
CPU 1 Vcore eventual - 1.34375

CPU VTT both boot - AUTO (at 1.350V) - So I should TYPE in: 1.35V - not leave on "AUTO" correct?
CPU VTT both eventual - AUTO (at 1.350V) - also TYPE in: 1.35V - not leave on "AUTO" correct?

Correct.

In the meantime will buy a copy of Windows 7 and install it and try it there and use Prime95; if that's what I should use, correct? Or should I use a different Torture Testing program? The Prime95 (the newest one) for Mac doesn't really do anything except make CPU 1's RAM run hotter than usual and I have high heat sinks. I stopped after 5 min of use on that torture test as I don't think it's allocating the test properly.



Again, forgive my ignorance, but what do you mean by this comment?

Read this article: http://www.techreaction.net/2010/09/07/3-step-overclocking-guide-bloomfield-and-gulftown/ This technique lets you isolate the variables of memory overclocking, BCLK overclocking (the CPU frequency multiplier) and uncore. Note that for this technique, you are going to temporarily keep your cpu multiplier turned all the way down (turning off speedstep and turbo boost), while you optimize memory, VTT and IOH for your target CPU frequency multiplier (BCLK). This takes the guess work out of where VTT and IOH need to be set. I find them generally lower than what Tutor is showing you, but I have a bit less memory installed, which does impact. For instance, my IOH is only 1.275 and VTT 1.325. It's also possible that "underclocking" changes those requirements, I don't know (wouldn't think so since things are at lower temps)


The reason the BSOD is useful is that folks have figured out what the BSOD codes mean for overclocking....I can make guesses from my OS X KP screens (which are quite infrequent, except when fiddling around with overclocking), but they are just that guesses.

 

[Tutor]

PunkNugget

I sugget that you follow braindeadfools's advice first for setting IOH and VVT voltages. My settings for those voltages are holdovers from my having began as an overclocker. VVT frequency settings (not VVT voltage) range from 4.8 to 6.4 and the higher I set BCLK and the VVT frequency, the higher I had to set IOH and VVT voltages. As you increase BCLK it will increase your VVT frequency just as it increases the CPU and memory frequency. The amount of the increase in those frequencies is as follows: Since the base ratio BCLK is 133 MHz, setting BCLK to 160 changes CPU, VTT and memory frequency like this - 160 divided by 133 = 1.203007518796992 or 1.2x. So if memory is set to 1333 MHz, CPU frequency is set to 3.3 GHz and VTT is set to 6.4 and you change BCLK to 160, then Memory's 1333 frequency value is raised to 1599.6 MHz (1333 x 1.2), CPU frequency is raised to 3.996 (3.33 x 1.2) and VTT becomes 7.68 (6.4 x 1.2). This is why you may have to begin setting memory frequency (depending on your memory's top frequency) and VVT frequency lower as you raise BCLK or raise the voltage for your memory or VVT.

 

[PunkNugget]

Continuing to put the finishing touches on some Sandy Bridge 6 [ http://www.cpu-world.com/CPUs/Core_i7/Intel-Core i7-3930K.html ], 16 [ http://www.cpu-world.com/CPUs/Xeon/Intel-Xeon E5-2680.html ] and 32 core ( [ http://www.cpu-world.com/CPUs/Xeon/Intel-Xeon E5-4650 - CM8062107184516 (BX80621E54650).html ] Pic w/o expansion chassis) systems for faster media production. These 4 particular 8-core 4650s base freg. is 2.7 GHz, but they turbo up to 3.5 GHz just like the 2680s. Benches are a few weeks off. So I'll continue to be in seeming hibernation, leaving voyagerd, Echrei, braindeadfool, PunkNugget and SR2Mac in charge of the class.

i7-3930K
That was the unit I was talking about before; it's your Sandy Bridge 6 system. Can you provide all the PC parts that you used for this machine? If I'm not mistaken this is the very one that is getting you a GB of 28,000+ correct?

i7-E5-2580
As this is a 16 core, (assuming that you're using 2 CPUs) what is this performance in this unit that you're getting?

Xeon E5-4650
WOW !!! $3,600 for each 4650? and you have FOUR of them ?!?!?! Little too steep for my wallet. I'm sure you must have got a good deal on these CPUs. Also knowing you I'm sure you'll beat the highest GB score of 83,226. Even though that guy's running a 12 processors.

 

[PunkNugget]

Correct.



Read this article: http://www.techreaction.net/2010/09/07/3-step-overclocking-guide-bloomfield-and-gulftown/ This technique lets you isolate the variables of memory overclocking, BCLK overclocking (the CPU frequency multiplier) and uncore. Note that for this technique, you are going to temporarily keep your cpu multiplier turned all the way down (turning off speedstep and turbo boost), while you optimize memory, VTT and IOH for your target CPU frequency multiplier (BCLK). This takes the guess work out of where VTT and IOH need to be set. I find them generally lower than what Tutor is showing you, but I have a bit less memory installed, which does impact. For instance, my IOH is only 1.275 and VTT 1.325. It's also possible that "underclocking" changes those requirements, I don't know (wouldn't think so since things are at lower temps)


The reason the BSOD is useful is that folks have figured out what the BSOD codes mean for overclocking....I can make guesses from my OS X KP screens (which are quite infrequent, except when fiddling around with overclocking), but they are just that guesses.

I will read through this and then get back to you with more questions as time progresses in the days ahead. Thanks...

 

[GermanyChris]

So I just built a new hackintosh with the discarded parts from the last one. (I'm a glutton for punishment) This time it was much simpler. It's in a Silverstone Lascala LC-10-E case my old p67 MOBO the Celeron and a GT430. How has mountain lion been treating you guys that upgraded? Should I stay with Snow Leopard?

 

[SR2Mac]

So I just built a new hackintosh with the discarded parts from the last one. (I'm a glutton for punishment) This time it was much simpler. It's in a Silverstone Lascala LC-10-E case my old p67 MOBO the Celeron and a GT430. How has mountain lion been treating you guys that upgraded? Should I stay with Snow Leopard?

It's like someone mentioned in another post...

"Honestly, you don't need it. The small "eye candy" differences are moot at best. As Tutor and ESPECIALLY ME, the "latest isn't always the greatest." if what you have is currently working, stick with it. I tried it and I even went back to 10.6.7 because I want to take advantage of the UC'ing features that you CAN'T do effectively, the way the "newer" code is written with 10.8. Again, I would stick with what you already have that's running stable."

 

[GermanyChris]

It's like I mentioned in another post...

"Honestly, you don't need it. The small "eye candy" differences are moot at best. As Tutor and ESPECIALLY ME, the "latest isn't always the greatest." if what you have is currently working, stick with it. I tried it and I even went back to 10.6.7 because I want to take advantage of the UC'ing features that you CAN'T do effectively, the way the "newer" code is written with 10.8. Again, I would stick with what you already have that's running stable."[\I]

It's running fine..

So I guess that's the answer.

 

[SR2Mac]

It's running fine..

So I guess that's the answer.

I wish I would have done that in the beginning; leaving well enough alone. Also, not that it means much but can you do a GeekBench score. Just curious what it is...

 

[GermanyChris]

I wish I would have done that in the beginning; leaving well enough alone. Also, not that it means much but can you do a GeekBench score. Just curious what it is...

3300-3500 depending..

If I put faster RAM (1866) in like before it moves into the 4K range.

I'll run a geekbench again in the next 120 or so hours I'ts got about 120 movies sitting in the handbrake Que.

 

[GermanyChris]

I paused the que..

The quad that replaced my 17,000 scoring i7 scores just a bit above thats with two processors and 4 cores :0)

Time does pass

 

[PunkNugget]

PunkNugget

I sugget that you follow braindeadfools's advice first for setting IOH and VVT voltages. My settings for those voltages are holdovers from my having began as an overclocker. VVT frequency settings (not VVT voltage) range from 4.8 to 6.4 and the higher I set BCLK and the VVT frequency, the higher I had to set IOH and VVT voltages. As you increase BCLK it will increase your VVT frequency just as it increases the CPU and memory frequency. The amount of the increase in those frequencies is as follows: Since the base ratio BCLK is 133 MHz, setting BCLK to 160 changes CPU, VTT and memory frequency like this - 160 divided by 133 = 1.203007518796992 or 1.2x. So if memory is set to 1333 MHz, CPU frequency is set to 3.3 GHz and VTT is set to 6.4 and you change BCLK to 160, then Memory's 1333 frequency value is raised to 1599.6 MHz (1333 x 1.2), CPU frequency is raised to 3.996 (3.33 x 1.2) and VTT becomes 7.68 (6.4 x 1.2). This is why you may have to begin setting memory frequency (depending on your memory's top frequency) and VVT frequency lower as you raise BCLK or raise the voltage for your memory or VVT.

Thanks for the info. I've been studying this stuff out today and hope to understand all of what BDF and you have just shared with me. BTW, what Stress Test Rendering app would you use for Windows 7? Thanks...

 

[PunkNugget]

Read this article: http://www.techreaction.net/2010/09/07/3-step-overclocking-guide-bloomfield-and-gulftown/ This technique lets you isolate the variables of memory overclocking, BCLK overclocking (the CPU frequency multiplier) and uncore. Note that for this technique, you are going to temporarily keep your cpu multiplier turned all the way down (turning off speedstep and turbo boost), while you optimize memory, VTT and IOH for your target CPU frequency multiplier (BCLK). This takes the guess work out of where VTT and IOH need to be set.

I read everything (as best as I could understand) and I have some questions. Starting with the first step (in Windows 7). I'll shut off SpeedStep & Turbo Boost, then am I to just set everything to it's initial default value (stock) and then set my BCLK (CPU Freq. Multi.) to 12? Because that's as low as it will go. Then will I know what the Memory, VTT and IOH are when I reboot and go back into my BIOS in the Voltage Configuration Menu (VCM)? Because I don't even know where to start to give them the proper voltage to begin with. Also, do I do it with or without VDroop? Once I get this done, then I'lll move onto the next question. Thanks...

PS - In relation to all of this stuff that you gave me, did you understand what Tutor is talking about with what he replied to me about when it came to this:

I sugget that you follow braindeadfools's advice first for setting IOH and VVT voltages. My settings for those voltages are holdovers from my having began as an overclocker. VVT frequency settings (not VVT voltage) range from 4.8 to 6.4 and the higher I set BCLK and the VVT frequency, the higher I had to set IOH and VVT voltages.

Just to get this straight, is the "VVT Freq" (or VTT Freq) the same as QPI Freq? Because that's the only place that I can see the range of 4.8GT to 6.4GT anywhere in the BIOS. The only other place that I can see the VTT Freq is in the VCM toward the bottom of the screen that says: CPU0 (and CPU1) VTT PWM Freq and that range is between 240 KHz to 634 KHz. So I don't think that's the right one that he's talking about.

As you increase BCLK it will increase your VVT frequency just as it increases the CPU and memory frequency. The amount of the increase in those frequencies is as follows: Since the base ratio BCLK is 133 MHz, setting BCLK to 160 changes CPU, VTT and memory frequency like this - 160 divided by 133 = 1.203007518796992 or 1.2x. So if memory is set to 1333 MHz, CPU frequency is set to 3.3 GHz and VTT is set to 6.4 and you change BCLK to 160, then Memory's 1333 frequency value is raised to 1599.6 MHz (1333 x 1.2), CPU frequency is raised to 3.996 (3.33 x 1.2) and VTT becomes 7.68 (6.4 x 1.2). This is why you may have to begin setting memory frequency (depending on your memory's top frequency) and VVT frequency lower as you raise BCLK or raise the voltage for your memory or VVT.

For the rest of the info (above) I'm starting to understand this a little bit better but still need time to absorb this, but will understand it better as I continue to learn this. I look forward to your answers as that will also provide the best clarity for me as I move forward... Again, thanks...

 

[braindeadfool]

I read everything (as best as I could understand) and I have some questions. Starting with the first step (in Windows 7). I'll shut off SpeedStep & Turbo Boost, then am I to just set everything to it's initial default value (stock) and then set my BCLK (CPU Freq. Multi.) to 12? Because that's as low as it will go. Then will I know what the Memory, VTT and IOH are when I reboot and go back into my BIOS in the Voltage Configuration Menu (VCM)? Because I don't even know where to start to give them the proper voltage to begin with. Also, do I do it with or without VDroop? Once I get this done, then I'lll move onto the next question. Thanks...

PS - In relation to all of this stuff that you gave me, did you understand what Tutor is talking about with what he replied to me about when it came to this:



Just to get this straight, is the "VVT Freq" (or VTT Freq) the same as QPI Freq? Because that's the only place that I can see the range of 4.8GT to 6.4GT anywhere in the BIOS. The only other place that I can see the VTT Freq is in the VCM toward the bottom of the screen that says: CPU0 (and CPU1) VTT PWM Freq and that range is between 240 KHz to 634 KHz. So I don't think that's the right one that he's talking about.



For the rest of the info (above) I'm starting to understand this a little bit better but still need time to absorb this, but will understand it better as I continue to learn this. I look forward to your answers as that will also provide the best clarity for me as I move forward... Again, thanks...

Yes, to establish stable bclk turn off all the stuff that makes underclocking work and turn the turbo ratio down....you are temporarily taking the cpu and memory "out of the equation" for overclocking.

Yes I understood what Tutor meant, read and understand the article and most will be clear. Yes, when he's talking about VTT freq he's meaning the QPI frequency. Leave the PWM fequencies alone....

Edited...poor reading on my part. "without vdroop"

 

[PunkNugget]

Yes, to establish stable bclk turn off all the stuff that makes underclocking work and turn the turbo ratio down....you are temporarily taking the cpu and memory "out of the equation" for overclocking.

Yes I understood what Tutor meant, read and understand the article and most will be clear. Yes, when he's talking about VTT freq he's meaning the QPI frequency. Leave the PWM fequencies alone....

Edited...poor reading on my part. "without vdroop"

Thanks for the input and the "edit" that you made. I know that I put down quite a bit of info for you to answer, so what I'll do is put a number to my questions and be as brief as I can as this might have been missed:

1) After I lower the BCLK to 12... "Then will I know what the Memory, VTT and IOH are when I reboot and go back into my BIOS in the Voltage Configuration Menu (VCM)? Because I don't even know where to start to give them the proper voltage to begin with..." Then do I work my way up a notch or down a notch while I'm stress testing these voltages if I'm UC'ing?

2)

Yes, to establish stable bclk turn off all the stuff that makes underclocking work and turn the turbo ratio down....you are temporarily taking the cpu and memory "out of the equation" for overclocking.

So after turning everything off do I initially start OC'ing the system to get the system stable before I start UC'ing?

 

[Tutor]

I read everything (as best as I could understand) and I have some questions. Starting with the first step (in Windows 7). I'll shut off SpeedStep & Turbo Boost, then am I to just set everything to it's initial default value (stock) and then set my BCLK (CPU Freq. Multi.) to 12? Because that's as low as it will go. Then will I know what the Memory, VTT and IOH are when I reboot and go back into my BIOS in the Voltage Configuration Menu (VCM)? Because I don't even know where to start to give them the proper voltage to begin with. Also, do I do it with or without VDroop? Once I get this done, then I'lll move onto the next question. Thanks...

PS - In relation to all of this stuff that you gave me, did you understand what Tutor is talking about with what he replied to me about when it came to this:



Just to get this straight, is the "VVT Freq" (or VTT Freq) the same as QPI Freq? Because that's the only place that I can see the range of 4.8GT to 6.4GT anywhere in the BIOS. The only other place that I can see the VTT Freq is in the VCM toward the bottom of the screen that says: CPU0 (and CPU1) VTT PWM Freq and that range is between 240 KHz to 634 KHz. So I don't think that's the right one that he's talking about.



For the rest of the info (above) I'm starting to understand this a little bit better but still need time to absorb this, but will understand it better as I continue to learn this. I look forward to your answers as that will also provide the best clarity for me as I move forward... Again, thanks...

Forgot to mention - at < 166 BCLK, I now keep QPI at 5.8. That's why I sometimes set the QPI voltage as high as I do 1.375 to 1.4, depending on the task at hand.
I have fan on rear CPU (CPU 1) because it is set to at least 2 steps less Vcore than is CPU 0 and H80 is on front CPU - CPU 0. Moreover, I've found that system and CPUs stay cooler by bringing in air from the rear to cool H80 and exhausting air from top of front and top of my modified Antec 1200s. I use two 4000+ rpm Sunon fans - one to cool H80 radiator and one on front above DVD drive, to exhaust from top front of case.

VVT (typo) = VTT = QPI. VTT PWM is something different. It is how the signal's wave is massaged or modulated. Changing the wave form's modulation can add to, as well as detract from, stability. So you can try it too so long as you test to see how stability is being affected by the changed setting. CAVEAT: less is more.

 

[GermanyChris]

I guess the OS does make a difference here is 10.8.1. The would be 1200 points changing from 10.6.8.