Gigabyte X38/P35/P965 (DS* DQ* S3) Overclocking and General BIOS tweaking Guide

[KnowEyeDear]

Nice work, thank you for your effort

[Lsdmeasap]

NP

I didnt create the guide, Bill Parrish @ [H] did.

But I knew All of us Gigabyte Users here could surely use the Guide Very Much


Hope it helps you, and Others. If not please feel free to post here or make a thread and I will be glad to try to help anytime

[Merman]

@ Merman

My image is for a 65nm XEON and has nothing to do with 45nm ones, and that just happens to be MY VID.

Yeah, I have seen and use RealTemp, But My temps are fine so I dont even look at them, every once in a while I will watch them in Everest, but since I own a license I can see all options in everest, so I use it for everything

As for you VID of 1.15, all that means is your CPU has been overclock tested by intel to be guaranteed to run at stock speed with 1.15 Voltage. it is in now way a limit, and is in now way stating that you absolutely have to use that to run stock. They often raise it a bit to ensure stability.

Ill have my Xeon E3110 Monday so By Monday night I will be able to tell you my VID and then what I need per my chip to run 4Ghz or so

I didn't get into this in the other thread so as not to hijack it so I will share my questions here.

You said that Core Temp gives the chip's vcore and on my E8400 chip it reads. 1.0375.

Real Temp vid 1.15v

Cpu-Z core voltage 1.056v

Everest core voltage 1.038

GA-P35-DS3L F8a bios
PC Health Status Vcore 1.076
MIT CPU Voltage Control 1.10

Before I set voltage control to 1.10v
MIT Normal CPU Vcore 1.15v
PC Health Status Vcore 1.204v

Now I uderstand each chip has its own vcore set at the factory and is not a limit to what the chip will take to become stable at overclock speeds and there is vdroop when the chip is being monitored but which is which???

Since the chip has its own vcore shouldn't the bios be set to this voltage if not overclocking???

The Intel Data sheet specifies different types of vcore, requiring different voltages, which I want to understand but haven't read the whole data sheet document yet. Maybe you know of a source or document that can explain this to a layman???

BTW Unclewebb, creator of RealTemp, specifically states and I quote:

"Better yet, just forget about temperatures. That's the least of ones worries with these chips. There's a huge amount of temperature head room, even when grossly overclocked. With Penryn, it's voltage headroom that people need to watch. Sorry for getting off topic but I thought this is info that overclockers need to know."

Not that core temps are that important but he makes a good case that both CoreTemp and Everest are reading them 10C too high for the 45nm chips. Everest lastest beta is now allowing Tjmax to be adjusted in preferences.

[Lsdmeasap]

Ahh this thread is here to help, no hijacking will ever be thought of. I posted it to help people, and anyone can post a question here or make thier own thread, whichever they feel is better

CoreTemp give you the default VID not the Vcore, that is different

VID is what intel has tested the chip to be stable at stock setting

Deafult Vcore is where Intel has set the Vcore Voltage to run at despite what they tested the VID to be

Vdroop is what your BOARD does to the voltages between idle and load

Vdrop is what your BOARD does to the voltages between what you set in the BIOS and what is used at post when in windows and at idle

Vtt voltage and Vcore voltage is what you need to watch with 45nm, as for Vtt voltage that is the termination point between the CPU and the MCH. Which most Gigabyte boards do not let you control. So I dont know if that is good or bad.

As for Vcore voltage just keep in mind as you have been reading, yes 1.45 or 1.5 as most said was still safe with 65nm is no longer safe area with 45nm. Most I have seen in testing are saying 1.4 is getting to be the max safe area with 45, and most trying to stay under that on air

[Merman]

Thank you for your explanation. I understand you are trying to keep it simple and that sometimes leads to confusion.

Let me ask you this: Does CPU-Z show the actual vcore reflecting vdroop in the number it reports???

Does Everest show Vtt???

Do you know what the CPU voltage in the MIT section of bios actually does or what its suppose to do???

Does it set the average or maximum voltage to use??? When I reduced voltage there, vcore definitely went down. I understand this is where to increase voltage if needed for a stable overclock???

The reason I ask is as I understand the Intel Data sheet and the VDR 11. document: They explain that VID is dynamic with the voltage regulator supplying the required voltage needed per a preset table with over and under maximums.

[Lsdmeasap]

CPU-z shows actual vcore, and will change with change to idle/load. If you look at it once you get in windows you will the the drop from what you set in the bios to idel voltage. Which is Vdrop. When you load the cpu you will see Vdroop which is idle to load drop

Everest may or may not show VTT, I know it does not if you can not set it on your board, so if someone with a DQ6 could answer if they can set it or not and in fact see it in everest then yes. But I do not have a setting for it so I cannot say, same goes fro NB voltages, I knwo those show because I have seen others who can set them post everest images, which makes me believe the same would go for Vtt

The CPU voltage option in MIT lets you set the CPU Vcore as expected, if you have a board with loadline calibration this will stay VERY close if not exact to what you set, when in windows at idle or load. If you do not have this option in your BIOS then there will be some differences due to Intel reference designs....There will be a drop from this initial setting to a Idle voltage a bit lower (Vdrop) and there will be a drop from Idle to load (Vdroop) per Intels design. Some boards are worse then others, some are great at having none of either. And then some have BIOS settings to overcome vdroop

It sets the max voltage yes, your board and bios limitations are where this may differ in what you get in windows and from idle to load

Yes you are seeing that correct in the Intel design sheets, VID does have a range, but that range is specific to a Family. Such as the core duo family, all core 2 duo's have a VID within 0.85V – 1.5V. Each specific chip has been tested and will have a set voltage Intel has decided that the chip will run stably at between this amount. Plus a little

[Merman]

Thanks again. After reading the Intel documents most of what I read makes more sense and you have helped to verifiy this.

Though I do want to question Vtt since you pointed out anand's refernce to it killing their $1,000 quad core by setting that voltage too high.

As you mentioned Vtt is voltage to the FSB. My DSL3 bios has a setting for "FSB OverVoltage Control."

Your answers imply these are not the same yet in my limited understanding they seem to be the same thing. Though I do understand the way MB manufacturer's label items in bios it could sometimes not be the same thing or one has to try to confirm that the item in bios is what you are looking for.

This article is about advanced control of the FSB for quad cord processors but as I understand it, Vtt is FSB voltage.

Theory of Operation - Increasing Target Performance


VTT, sometimes referred to in the Basic Input/Output System (BIOS) as the FSB Termination Voltage, provides the low level signaling bias needed for the processors, chipsets, and all other devices on the bus to communicate. The FSB is the electrical interface that connects the processor to the chipset (also called the processor system bus or the system bus). All memory and I/O transactions as well as interrupt messages pass between the processor and chipset over the FSB.

Adjusting A/GTL+ Levels for Increased FSB Signaling Margins and Overclocking - The Tech Repository Forums

I would also like to share this document for anyone interested in this discussion. I only found these references after getting Lsdmeasap's excellent explanations. They seem to be from Intel and surprising me they are about overclocking.

Intel Processor Power Delivery Design
Guidelines and Specifications: Vdroop Explained

Intel Processor Power Delivery Design Guidelines and Specifications: Vdroop Explained - The Tech Repository Forums

[Merman]

I would like to share one more source as this site has helped me so much. Anand's article should be read in full but here is reinforcement of what Lsdmeasap has said in an easy to understand graph.

AnandTech: Overclocking Intel's New 45nm QX9650: The Rules Have Changed

[Lsdmeasap]

Vtt is not FSB voltage.

It is the termination voltage between the FSB and the MCH, something Gigabyte boards do not allow us to control, maybe the DQ6 models have it but I have not seen the BIOS for one lately. I do know the DS4's and under do not have the option, so you are safe and cannot increase it too high

[Merman]

Yes I saw that in the Anand article but still think that definition is too simple. If you read the Intel document I referenced by Kristopher Boughton and the quote of "Theory of Operation - Increasing Target Performance." Vtt or FSB Termination Voltage is needed for all the devices on the FSB to communicate.

So what does the option "FSB OverVoltage Control" on our Gigabyte MB do???