DFI LanParty NFII Ultra B Voltmods

[celemine1Gig]

The DFI LanParty NFII Ultra B is said to be the best NForce2 based motherboard (or even the best Socket-A board overall).
It has all the features that lots of enthusiasts all around the world were dreaming of seeing packed into one (nearly) perfect motherboard. Those massive advantages are responsible for the excellent reputation of this mainboard, but for some of the users out there this motherboard is not extreme enough, yet. Those users always try to make the best even better, by modding it, thus it matches all their needs (i.e. extreme voltages and extreme stability).
I wrote up a little guide which describes all of the mods for the DFI Lanparty motherboard (and the DFI Infinity NFII, as the layout is the same).

Required parts

At first, I'll list the parts that I used:

• one 50K (trimmer-) potentiometer for the VCore-Mod
• one 50K (trimmer-) potentiometer for the OVP-Mod (overVoltage Protection)
• one 50K (trimmer-) potentiometer for the VDD-Mod
• one 100K (trimmer-) potentiometer for the VDimm-Mod
• one 50K (trimmer-) potentiometer for the Southbridge-VMod
• three SMD/SMT 4.7K resistors (size 0805) for the VDroop-Mod
• a good soldering iron (Ersa 25W in my case)
• rosin core solder and solder flux (for example "colophony")
• some cables (I used 1mm diameter cabling, made from copper strands, normally used for hifi systems)
• some heatshrink tubing and hotglue
• and perhaps some isolating protection lacquer
• heatsinks and thermal epoxy (an alternative to the thermal epoxy would be to buy 5-minute two component epoxy and then mix that with a thermal compound; I used that and it's working fine)

First, cut off or break off one of the two outer legs of all potentiometers, because only two contacts are needed [the middle contact (signal) and one of the outer two pins (ground)]. The third one is useless and could be in your way while working on the other two legs, or could interfere with some parts on the mobo.

Afterwards, adjust the potentiometers for VCore-, OVP-, VDimm- and VDD-Mod to the maximum resistance. The potentiometer for the Southbridge-VMod needs to be set to ZERO Ohms because that Mod leads to increased voltage with increased resistance, in contrast to the other mods. Those are the values to start with - they are very important!

VCore-Mod

Datasheet of the chip:

http://www.intersil.com/data/fn/fn4765.pdf

Connect the middle pin of the 50K potentiometer to Pin #7 (FB) of the HIP6301 chip and then connect the outer pin of the potentiometer to Ground.
Pin #9 of the HIP6301 is a Ground pin, but we will need to solder a cable to the next Pin #10 for the OVP-Mod. I didn't like the idea of soldering two cables right next to each other. That would've been very hard, and why do it the hard way, if there's an easier way right around the corner. For Ground I just used the Ground point from a left-empty solder-pad ("EC18"), where DFI had planned to put a capacitor, but cancelled that idea obviously (solder point in the area that is marked white, is GROUND). Use that point as Ground for both the VCore- and the OVP-mod, it will have no negative impact on the mods.

OVP-Mod

Same chip, so no new datasheet link needed (still HIP6301).

The OverVoltage Protection-Mod is only needed, if you are going to run a VCore higher than 2.0V.
As I already mentioned above, the OVP-Mod involves connecting a 50K potentiometer from Pin #10 of the HIP6301 chip to Ground.
Just connect the outer pin of the potentiometer to the Ground point mentioned above (left-empty solder-pad, not far from the HIP6301 chip). Then connect the middle pin of the pot to Pin #10 (VSEN). Well, that's it and you've finished the VCore and OVP mods.

Picture for both VCore- and OVP-Mod

VDroop-Mod

As many of you already know, the DFI board has some quite high VCore fluctuations under load. That's why some smart guys figured out a VDroop-Mod for this board, to reduce those fluctuations.
This mod is rather delicate as you need to remove 3 SMD/SMT resistors on the board in a cramped area and replace them by SMD/SMT resistors of different values.
The resistors, marked in the pic, need to be removed and then you solder in one of the SMD/SMT 4.7K resistors in each of the marked locations.
I'd advise you to order more than just the three needed resistors, as you may need to try that mod more than once before you succeed. Sometimes one or two resistors get damaged (due to overheating or whatever), so be sure to have a replacement!

VDD-Mod

Datasheet of the chip:

http://www.national.com/ds/LM/LM158.pdf

Connect the middle pin of the 50K potentiometer to Pin #6 (Inverting Input B) of the LM358 chip. Then connect the potentiometer's outer contact to Pin #4 (Ground/GND).
The measuring point for VDD is located in the top right corner of the pic. It's the right leg of the VDD mosfet.

VDimm-Mod

Datasheet of the chip:

http://www.semtech.com/pdf/sc2616.pdf

The middle pin of the 100K potentiometer normally would need to be connected to SC2616's Pin #1 (FB). But as the chip has very tiny legs/contacts, that would be nearly impossible to do with normal equipment. Thus we trace pin #1 to a SMD/SMT resistor just next to the chip (marked in the pic). Now you need to connect the potentiometer's middle pin to the side of that resistor, facing the greenish capacitor next to it, as seen in the pic. After that you have to connect the outer pin of the potentiomter to Ground. Just like when doing the VCore-/OVP-Mod, I used an empty solder pad ("EC57") as Ground. Again, it was planned to be used for a cap and was then left empty in the final product (see the pic for details). Measuring point for Vdimm is on the second mosfet from the left, under the RAM slots. Make sure to take a look at the pic for the correct leg, as it depends on how your board is placed on the table. That way, you can't go wrong.

Southbridge-VMod

For that last mod, again a 50K poti is needed. To supply more voltage to the southbridge chipset, it's required to remove the SMD/SMT resistor "R151", next to "VR4" (looking like a mosfet, right next to the second PCI slot, counting from the top). You just desolder that resistor and connect the upper solder-point, which is now empty (after having removed the SMD/SMT resitor), to the middle pin of the 50K potentiometer. Afterwards, you connect the outer pin of the potentiometer to a Ground point nearby. I used the solder-pad ("EC32") next to the battery, right under PCI-slot #3.
The measuring point for the southbridge voltage is the upper contact of the capacitor "EC42", right next to the other soldering-points.

Overview & additional modifications

That’s all the info needed to do the mods!

I did the following additional modifications to my board:

• lots of heatsinks on all kinds of chips on the board. VERY important: Provide some cooling for the SC2616 VDimm regulation chip and the VDD-Mosfet, as they get extremely hot (~70°C or more; burnt my finger on those). I cut up lots of heatsinks (mostly old P1 50x50x15mm sinks which can be aquired for only a few cents today) and used thermal epoxy to put them on. I only screwed down the northbridge heatsink.
  
  
  
• additional cabling to connect a second PSU. One cable for PS-ON (green cable on the PSU) and one for Ground (black cable on PSU). This makes a second PSU, connected to those two cables, turn on exactly at the same time as the main PSU.
  
  
  
• Northbridge and Southbridge were lapped and I put heatsinks on all those chips that I thought would benefit from it. I first lapped the heatsink base, and then put sandpaper on the bottom of those heatsinks with double-sided tape. Then I sanded the chipsets with the prepared heatsink, until it was flat, i.e. the print on the chip was fully gone and it was flat to the eye.
  
  
  
  
  
• additional capacitors on the backside of the motherboard. Those provide higher stability on high overclocks. BUT, be sure to use LOW ESR caps (or at least 105°C rated caps), keep the leads/cables as short as possible when soldering them in and don't use too much of them. Some additional caps can help, but too many will hurt.
  
  

I’ve got to thank Lastviking and all the other members of the xtremesystems.org forums (and anyone else involved) who helped in developing all those mods! Without their help it would have been much much harder to write this article.
Lastviking's "DFI Lanparty & Infinity FAQ" on the xtremesystems.org forums already includes nearly all of the mods that I described in the text above, so head on over there to view the original if you want. My goal was to make a guide with better and of course more pics, thus making it easier for you to follow. I hope I could accomplish that goal.

Warning:
All modifications are done at your own risk! I am not responsible for any damage caused by the mods!

I did the VDroop mod and it caused the center pair of mosfets (with heatsinks!) to heat to the point where the solder melted and they slid downward.

It was prime stable... for the 5 minutes it survived.

All I can say is:

If you don't know what you're doing and what the risks are, then stay away from these mods!

You did something completely wrong, if the mosfets really heated up that much.

[Anarion]

Huh!? after this mod how Supposed we put MB back on case!

i don't know is it great or not but obviously ain't neat .

[wazzledoozle]

Originally Posted by Anarion

Huh!? after this mod how Supposed we put MB back on case!

i don't know is it great or not but obviously ain't neat .

Use taller screw mounts under the motherboard.

[Anarion]

nice , but how about side connectors of mb , u supposed where to fit em !?

[celemine1Gig]

Those mods are absolutely optional. You don't need to do them all. If you don't know how to solve the "mouting my motherboard in the case" problem, well then don't do the cap mod. It's as easy as that. I even removed the cap-mod mysef after some time, because I didn't see any improvement with it.
BTW, I cut holes in my motherboard tray, to fit the board in the case without any problems.

[Anarion]

nice ,

btw i have a question if, can i ask , about soldering, how did u do that , i mean so neat,precise,great. ... (wow in such small things how did u do that , alas )

i some times try do solder some bigger things & face prob .

[celemine1Gig]

Originally Posted by Anarion

nice ,

btw i have a question if, can i ask , about soldering, how did u do that , i mean so neat,precise,great. ... (wow in such small things how did u do that , alas )

i some times try do solder some bigger things & face prob .

Of course you are allowed to ask. That's what the forums are there for.
It's nearly all about practice. Start with easy soldering jobs (cables, then old hardware and so on). Slowly work your way forward.
I couldn't solder very well at the beginning, and I don't consider myself a soldering pro today either. It's OK, but I'm far from being perfect.

So, start with simple things and keep on working on your technique. That way, it won't take too long until you'll be able to solder SMD chips like that.

Well, and one factor that needs to be mentioned is the soldering iron. If you got a good one, it's much easier, and if you got a bad one, it's damn hard (yes, even for me ).
I don't use a soldering station or even special SMD soldering iron or something like that. As written in my how-to, I used an Ersa 25W Soldering iron (ERSA Multitip C25) with an Ersadur longlife soldering tip (about 30$ for the iron and the tip together) for all the mods described in the article. I use that iron for nealy all my hardware mods, and I didn't face a single problem with it until today.

So, good luck. And, please don't start your soldering career with trying to solder SMD/SMT parts. This won't work for sure. Better take your time and do it well. That's my motto most of the time.

[Anarion]

tnx for ur experiences,learning, specially for favor , mass, even didn't bother themselves to answer such questions
(specifically coz they didn't want share their proficiency skills,techniques )

btw, i saw some "ColdHeat™ soldering iron" soldring device which (Additional tips are $9.95 (USD) (Half the price of the iron) ) http://www.ocwizard.com/index.php@op...id=33&Itemid=2
IMHO , it is realy great , ain't it !?

[Urlyin]

Nice work and excellent article Celemine1Gig ...

[celemine1Gig]

Thx, I hope I can make my future articles even better. There are some points that need to be improved next time.

@Anarion:

Well, the idea behind the cold-heat soldering iron is good, but for use on motherboards it's not really a appropriate solution. I read a review and some user experiences and the general opinion was: "Good for soldering wires etc., but not really useable on motherboards or other hardware components for vmods and such."

[dopeyman]

@ Celemine1gig: the Cold Heat irons create heat by way of arcing electricity between the two points of the tip through whatever it is applied to. Now, I have never read of anyone using one on a computer part like this, but it's possible that it will not damage anything because the electrical flow does not, I think, travel anywhere past the tip of the iron. I personally use a fine tip 15W grounded iron which is perfect, but in a pinch a 25 or even 35 watter can get the job done, provided you have more steady hands than I

Anyhow, I must say that I have not done any of the above mods, so I have not witnessed the effects yet. Let me get that across that I am not an expert with these mods, so what is below may be incorrect, but I would like to bring to your attention a couple of discrepancies I have found with it and an originating thread I first found about these mods, because this is a nicely laid out article with great clear pics as visual aid.

First is that the article shows that the three SMD resistor replacement mod (3.3~5.2K to replace stock 2.2K) is the VDroop mod, but the thread in question shows these resistors to affect the Over Current Protection, which results in worse fluctuations than stock without the VDrop mod that involves using one leg of a 50K pot on the same VR pin as the VCore mod (pin 7) with the other leg on the end toroid core, and reducing resistance to stabilize the voltage, but will also reduce overall VCore, even below the BIOS setting, so the VCore mod is required to offset this.

Second is that the Over Voltage Protection mod, a.k.a. VSense, is required for >=2.1v and not <2.1v as in the article.

The thread by Vlad Draculea here:
http://www.xtremeresources.com/forum...ad.php?t=31166

Lastly, I would like to ask if lapping the northbridge gained you anything because I've tried everything from endless alpha timing tweakage to the pin mod to default FSB @ 166 and even voodoo magic, and my board just won't run well above 220MHz with a gig of BH-5 (yes, tried CPC off and loosest timings possible and three different good PSU's). Right now I have a lapped Zalman ZM-NB32j with a 40mm fan on the NB and it did jack, so maybe lapping the chipset itself might help. Strangely, Memtest will run all day without any problems at above 230MHz, but either Windows won't boot, or 3D crashes to desktop. The 166 FSB pinmod just made it so that parts of levels disappear in the old UT and UT2k3 and eventually freeze at above ~215MHz rather than always CTD

[Anarion]

@dopeyman , very useful

About the cold-heat: Try it and then we'll see if it does any harm to hardware parts. I sure won't be the one to test that.

Originally Posted by dopeyman

...
First is that the article shows that the three SMD resistor replacement mod (3.3~5.2K to replace stock 2.2K) is the VDroop mod, but the thread in question shows these resistors to affect the Over Current Protection, which results in worse fluctuations than stock without the VDrop mod that involves using one leg of a 50K pot on the same VR pin as the VCore mod (pin 7) with the other leg on the end toroid core, and reducing resistance to stabilize the voltage, but will also reduce overall VCore, even below the BIOS setting, so the VCore mod is required to offset this.

Second is that the Over Voltage Protection mod, a.k.a. VSense, is required for >=2.1v and not <2.1v as in the article.

The thread by Vlad Draculea here:
http://www.xtremeresources.com/forum...ad.php?t=31166

Could be that it's overcurent protection and not Vdroop, but according to the datasheet this should be Vdroop if I remember correctly. I don't own the board anymore, so I won't do any further research.

And about the OVP, I don't really get what you are talking about. In my article it clearly says "for VCore higher than 2V". So what?

Please quote my original article if I'm missing something.

Originally Posted by dopeyman

Lastly, I would like to ask if lapping the northbridge gained you anything because I've tried everything from endless alpha timing tweakage to the pin mod to default FSB @ 166 and even voodoo magic, and my board just won't run well above 220MHz with a gig of BH-5 (yes, tried CPC off and loosest timings possible and three different good PSU's). Right now I have a lapped Zalman ZM-NB32j with a 40mm fan on the NB and it did jack, so maybe lapping the chipset itself might help. Strangely, Memtest will run all day without any problems at above 230MHz, but either Windows won't boot, or 3D crashes to desktop. The 166 FSB pinmod just made it so that parts of levels disappear in the old UT and UT2k3 and eventually freeze at above ~215MHz rather than always CTD

Too long ago since I had the board here. I only remember that it was stable at 260Mhz. Can't tell you more as I modded the board right after I got it. Did no tests with the board still at stock. Experiment with the mods and then see which help in your case and which don't. I'm no magician, so I won't be able to tell you what will help in your case. Fiddling around with all parts is the way to go, if you don't have a suspect that you blame the bad OC on.

Good luck with you board.

[celemine1Gig]

The answer above was written by me. Damn forum here let's you write replies without prompting you to log in. I often forget that.

BTW, one last thing to add:

Often, BIOS is the key to stable overclocking on that DFI board. Try lots of bios versions and perhaps you'll find one that will let you overclock higher than before. Had this happen to me often on Nforce2 boards. So give it a try.

BTW, had a look at the datasheets today. Vdroop is part of the Overcurrent protection. The resistors are connected to the current sensing pins. By changing the resitor values, we let more current flow through and decrease Vdroop that way. That's all. And that's why some call it OCP-mod and some vdroop-mod.

[dopeyman]

Originally Posted by celemine1Gig

I sure won't be the one to test that.

hehe, such is the response I've only seen about Cold Heat on a motherboard I think I'll leave that hot potato on the table!

Could be that it's overcurent protection and not Vdroop, but according to the datasheet this should be Vdroop if I remember correctly. I don't own the board anymore, so I won't do any further research.

hmm, I wonder if they may be related..? For example, I think the VDroop mod for the NF7-S involves three resistors (tictac mod IIRC) and can even be done with a pencil, and the last of the three resistors overvolts (possibly relieves OCP a bit?) VCore. --Just saw your update on the DS, that's a great explanation, thank you

And about the OVP, I don't really get what you are talking about. In my article it clearly says "for VCore higher than 2V". So what?

Please quote my original article if I'm missing something.

Sorry about that, I meant that the Vlad thread discussed that OVP is required for more than 2.1 and not 2.0 that the article says. In the BIOS, it would show as a max of 2.08 before the OVP would kick in. That .1v might be just what some users need without adding another pot for OVP *shrug* Just something I noticed.

Too long ago since I had the board here. I only remember that it was stable at 260Mhz. Can't tell you more as I modded the board right after I got it. Did no tests with the board still at stock. Experiment with the mods and then see which help in your case and which don't. I'm no magician, so I won't be able to tell you what will help in your case. Fiddling around with all parts is the way to go, if you don't have a suspect that you blame the bad OC on.

Good luck with you board.

Wow, that was a nice OC! When I got mine I was hoping for 240, maybe 250 with CPC off because of my dual-banked BH-5 sticks, but it has been an uphill battle >8) I finally decided to scrap the warranty and just hardwire it which is what made me interested in these mods, to try for some better CPU speeds because my 1700+ can do more, just needs some more of and stable juice.

Often, BIOS is the key to stable overclocking on that DFI board. Try lots of bios versions and perhaps you'll find one that will let you overclock higher than before. Had this happen to me often on Nforce2 boards. So give it a try.

Thanks for your insight and wishes, I think I'll have to end up tying a BIOS onto a stick and see if it'll chase after it.

BTW, had a look at the datasheets today. Vdroop is part of the Overcurent protection. The resistors are connected to the current sensing pins. By changing the resitor values, we let more curent flow through and decrease Vdroop that way. That's all. And that's why some call it OVC mod and some vdroop mod.

Interesting, thanks for going through it. I like knowing as much as possible about mods before I do 'em so this is a great help.

[skinnie]

people sorry to put thi thread up,but I did the vdimm mod to my board [no me,a friend of mine]




but now I notice that my ram [old skool bh5 ocz's] need much more volts to be stable..for example,before the vmods I needed 3.0v for 233 prime stable and 3.3v for 234 memtest stable,
now I need about 3.3v do 230 stable (still testing :X ) any idea?the thimings and alphas are the same,the bios is the same,the mems are the same..everything is equal..
and now the system is watercooled...
the only thing that I am seeing is that I "lapped" the sb..not heavy llaping,just to take of some superglue..that it had..

[eidairaman1]

skinnie nice mods n all but its too much effort for me

[ZenZimZaliben]

so after all of these mods, what was the end result?

[eidairaman1]

lets see, stability, high clocks, since Not many were able to Push AXP when it was in market, i also think the major limiting factor of CPUs is the Chipset.

[Craigleberry]

Holy crap batman that is crazy stuff.