DFI vdroop mod

[STEvil]

To those who have done it: What size resistor/VR did you use?

All I have spare is a 10K VR and i'm wondering if this is high enough (recommended is 50K VR) that i'm not going to fry anything but I can get my vcore somewhat stable.. the bounce in it is rediculous :rolleyes:

[uwackme]

You could always get a 33K resistor, and use in parallel with the 10K pot for the mod....for safety sakes.

[SAE]

I used a 4.75k resistor, you can go down to 1k if you want. At least vlad draculea (the developer of this mod) states that. I don't have probs, but remember: the lower the vdrop resistance, the lower the actual vcore. So you'd have to connect the vcore mod too. And to ensure stability you just have to drop the vcore to 1.825V in bios, and then turn the pot (50/47k).

P.S. Didn't know you'd start a new thread for that :confused:

[jonspd]

So can you do the vdrop without doing the vcore if let's say you use a 10K VR? Also I think someone need's to clear up the mod alittle for I have read it many time's and am still lost.

[STEvil]

I wouldnt mind losing some vcore, as even setting mine to 1.75 still gives me nearly .2v variance... its worse the higher FSB I try for, too... 2250 @ 225 1.8v is prime stable vs. 2150 @ 238 1.8v prime stable for about 6 hours..


Since it seems you lose vcore as you lower resistance of the vdroop mod could this be what DFI did to put the .15v mod in place to begin with? Would shorting it out completely (or nearly) and then doing our own vcore mod clear up these problems?

[SAE]

Originally posted by STEvil
I wouldnt mind losing some vcore, as even setting mine to 1.75 still gives me nearly .2v variance... its worse the higher FSB I try for, too... 2250 @ 225 1.8v is prime stable vs. 2150 @ 238 1.8v prime stable for about 6 hours..


Since it seems you lose vcore as you lower resistance of the vdroop mod could this be what DFI did to put the .15v mod in place to begin with? Would shorting it out completely (or nearly) and then doing our own vcore mod clear up these problems?

Remember. You won't see the lower vdrop in bios as the readout chip is cr*p... But you notice it in stability :) Set the pot to 5k and go from there. Make sure you know where the max/min of the pot is ;) To make it safe just add a 1k fixed res in series to the pot so the onboard circuit cannot burn out.

The DFI mod can be undone, but don't ask me how... ;) Gaz (Cactus Jack) did it accidently and was fine after that. It should work if you found a way to disable it without damaging the hardware :D


@jonspd

Yeah. You can do the vdrop on its own. you would not need any other mod unless you wanna use 2V or more. So just solder a wire from pin7 of the HIP to a fixed 1k or 2k (or sth similar) and the to a 10k pot (middle leg). Then solder an additional wire to one of the outer legs of the pot (determines the direction voltage in-/decreases when turning) to this leg of the (rightmost) toroid pointing to the socket... Done :thumbsup:

[STEvil]

the DFI mod works through PGOOD (pin 1) I believe.. Pin10 also plays a roll in this, but it is only for low vcore situations.

EDIT

There is also some said about this on pages 1 and 10 of the PDF.. coincidence? heh..

What jack may have done is burned out the circuit which senses overvoltage.. which corresponds to PGOOD.

[SAE]

Originally posted by STEvil
the DFI mod works through PGOOD I believe.. Pin10 also plays a roll in this, but it is only for low vcore situations.

If you can get it disabled then just tell us :D

I don't understand these datasheets very well, hehe ;)
(would have to study it more intensely)

[jonspd]

Ok just to make sure I got this correct in my head.


SMD grabber to pin 7 counting counterclockwise from the dot on the chip to a 1-2k ohm fixed resistor to the middle leg of a 10k vr then the leg closest to the turning part of the vr to a ground?

or not to ground to last leg pin 10 of the same chip?


P.s. I really need this mod when set to 1.9 in bios I get 1.82-1.95 blah.

[STEvil]

To the side of the torroid (there are several torroids, its the one closest the northbridge iirc) closest the CPU, not ground.

There is a good pic on the last page of the dfi mod thread in the motherboard vmod section.

[SAE]

Originally posted by STEvil
To the side of the torroid (there are several torroids, its the one closest the northbridge iirc) closest the CPU, not ground.

There is a good pic on the last page of the dfi mod thread in the motherboard vmod section.

Thx pal :D :thumbsup:

The rightmost torroid's leg closer to the cpu. Do not ground it as it would work like a vcore mod... and would definately not stabilize the voltage.

[jonspd]

The green thing with copper wraped around it?

[STEvil]

yup

[jonspd]

Ok all done time to see how much it change my flux in vcore but I have one last question should I change the 10k vr resistisants or leave it @ 10k?

[jonspd]

So far so good went from 1.9= 1.82-1.95 to 1.9=1.86-1.90 thank's for all the help now If I can just get back to figuring out a good bios version I like.

[STEvil]

6/19 came out today.. heh

[SAE]

Originally posted by jonspd
Ok all done time to see how much it change my flux in vcore but I have one last question should I change the 10k vr resistisants or leave it @ 10k?

You can set it to 5k as well if you want to...