ep45 Ds3R question regarding bios functions

[harry23lim]

i want to know something about what does this things do?

do i need to tweak this things in overclocking?( only the things that i dont know in the following:)

Cpu V core - the core voltage of the processing chip i know this already
CPU termination - VTT(fsb voltage) but i dont know what this do. so?
Cpu PLL - i dont know
Cpu reference - i dont know
Cpu Reference2- i dont know

MCH/ich- North bridge voltage
mch reference - i dont know
mch/dram reference- i dont know
ich/io - South bridge voltage

dram voltage - the voltage of the ram. i know this already
dram termination - dram VTT( i dont know what this do)
channel a reference - i dont know
channel b reference - i dont know

i want to know this because i want to undertand my board fully so i can overclock easily.

[Lsdmeasap]

Re: ep45 Ds3R question regarding bios functions

This is the best place I could find with info that is written clearly, but it is The German Gigabyte Support Site >>>

http://62.109.81.232/cgi-bin/sbb/sbb.cgi?&a=show&forum=1&show=7573&start=0#1

And here is a German Guide which is very nice, each post is a little about each section >>>
JZ Board

If you would like I will post some "Summary's" of what they are when I get home tonight the best I can, if you would like me to let me know

[harry23lim]

Re: ep45 Ds3R question regarding bios functions

Lsdmeasap

im a filipino/chinese. english is most likely my second language. i hope you explain it to me. because i can't understand german.

[Lsdmeasap]

Re: ep45 Ds3R question regarding bios functions

Ahh, well I dont understand german either. And Would have it translated as well to english

I can explain the terminations and PLL to you tonight when I get a second but the references is harder to explain.

I will post some info tonight

[harry23lim]

Re: ep45 Ds3R question regarding bios functions

ok thanks ill be waiting. and im also researching for "others" not only us, should know what does that things do ^_^

[harry23lim]

Re: ep45 Ds3R question regarding bios functions

1 Down

FSB Termination voltage, which is the termination voltage of the host bus but, more importantly, also the bus supply voltage. Intel’s specifications allow voltage levels between 0.83 and 1.65 on the termination buffers, however, keep in mind that the voltage is the same as the bus supply voltage, which is limited to a maximum of 1.29 according to Intel’s specifications. We did find that increasing the FSB termination voltage caused the CPU temperature to increase, at least compared to the “Auto” setting. Consequently, also the CPU throttling kicked in earlier and, particularly in graphics applications, the system had a tendency to freeze, followed by ATI’s VPU recovery message blaming ATI’s drivers.

Keep in mind here that the only thing changed was the manual setting of the FSB termination voltage, while all other system parameters remained identical. On the other hand, the strange behavior of misreporting benchmark results could be completely eliminated, with the caveat that higher bus frequencies required higher termination … er, bus supply voltages. In so far, all of this makes sense now. The Prescott with its much better utilization of the bus puts more strain on the bus itself including the clock domains – which, therefore heat up faster and consequently, need more voltage. On the other hand, a higher bus supply voltage also causes the bus to run hotter and, in addition, may cause more passive power drain from the CPU- which consequently will run hotter and throttle earlier

[harry23lim]

Re: ep45 Ds3R question regarding bios functions

Ich/Io is the southbridge!! :) and do not need to be adjusted because pcie is locked @ 100 am i right Lsd? so it means its not related to oc'ing

[harry23lim]

Re: ep45 Ds3R question regarding bios functions

i have an idea on Cpu PLL - "they" said that you must set this below 1.9V because your chip will die easily

[Lsdmeasap]

Re: ep45 Ds3R question regarding bios functions

Ya, ICH/IO is the Southbridge Voltage. Some people who use Crossfire or Bad arse cards do add some voltage there, but it is generally not needed

I suggest CPU PLL MAX to be 1.6, with suggested max of 1.55, so yes 1.9 is WAY to much I think. Who is using that? I saw you commented this on another post as well, No one I have seen post has 1.9 as a setting. Just wondering why you posted that on the other thread

CPU termination - VTT MAX Suggested 1.5V and it should ALWAYS be set below Vcore. 1.45V is the max suggested for 24/7 use, 1.5 for bench's or short runs ONLY. Best to keep below 1.45V

Well here is what a hour on google has brought up, hope this helps you. I will know more when I get my P45, but for now this is all I can say a bunch of quoted info.

When I get my P45, I will post what does what in real world terms towards overclocking and how it helps/hurts

CPU VTT and Reference voltages

CPU VTT Voltage is the termination voltage for data lines used to interface the MCH with the CPU die(s) via the Front Side Bus. Higher values can provide additional FSB overclocking margin, especially with 45nm dual-core processors and quad-cores CPUs in general. We have never found any additional gains to be had above 1.36 when using air- or water-cooling. Setting Auto should default to 1.10V for 45nm CPUs and 1.20V for 65nm CPUs. Knowing this, there appears to be a dead band between 1.10V and 1.20V where intermediate values cannot be selected - we are working with ASUS engineering to get this corrected.

CPU VTT is the most important setting for stable overclocks. The CPU VTT Voltage sets the CPU termination voltage, allowing for a 1.5V maximum. Using this voltage in combination with the CPU VCore voltage setting can greatly enhance the system stability while overclocked. The system memory reference voltage is split between settings, the controller reference voltage and one option each for the two memory channels. In all cases, the base reference voltage can be set to a maximum of .03V over half of the set memory voltage.

"In summary, the CPU VTT controls the CPU termination voltage. It reduces the number of false electrical signals by providing a form of "ground" to pull out these false currents. ."

VTT relates to the FSB termination voltage, which is the actual voltage that flows through the main data bus of the entire motherboard.

CPU VTT and FSB VTT are different animals: the former is the termination voltage on the CPU end, and the latter is the termination voltage on the northbridge end. Setting .5v less than the NB voltage would make sense for FSB VTT, but less so for CPU VTT. I'm sure that higher voltages for CPU VTT would work as well as lower given that both are stable. I suspect, however, that higher does not equal better though

Some in depth reading on Vtt and GTL Reference Voltage (GTLREF Is the CPU References) >>>
Global

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

AnandTech: ASUS Striker II Extreme: Mucho Bang, Mucho Bucks

Vtt Warning >>>
AnandTech

CPU PLL

CPU PLL Voltage. Selecting a higher PLL (phase lock-loop) voltage may help the installed CPU clock higher or may assist with maintaining stability when operating at higher FSB speeds. Most users will find they do not need to set this to anything above 1.50. Exercise caution when experimenting with higher values as there have been reported cases of CPUs losing cores after being subjected to voltages in excess of about 2.00V.

Please read these for Dram VTT, and Dram Reference

http://www.elpida.com/pdfs/E0678E10.pdf

http://www.elpida.com/pdfs/E0593E10.pdf

[harry23lim]

Re: ep45 Ds3R question regarding bios functions

i advised to set it manually( the pLL) because when leaving it on auto the voltage is way to high. i noticed this on Easy tune my Cpu PLL voltage is set on Auto and is set to 1.85v LOL thats almost 1.9v im only running @ 356 fsb. the auto settings adjust way more than what you need.

[Lsdmeasap]

Re: ep45 Ds3R question regarding bios functions

Ohhh! Really, well thanks for the tip. What do you normally set it to, 1.5V?

Ya, Auto is usually not good for much of anything.

Thanks again for the tip, I will soon have a DS4P here next week or so