Step by Step VDD mod 8RDA+

Could you guys make a step by step vdd mod guide. I am confused on what to buy at the RadioShack. Links would be great as well. I would like to not solder but if its necessary then what the hell. I heard SMG grabbers are not a good perminant solution. I just put a P$ HSF on the chipset so cooling is taken care off. Please post pics of how urs turned out.

.EDIT IMPORTANT: For clarification here it is. The yellow cable is hooked up to the middle pin on the vr and the black cable is hooked up to the outer pin on the side with the adjustment screw. If u do it this way then turning LEFT gives more resistance and LOWER (safe) voltage and turning right give high voltage. If u don't have a multimeter u can hook it up as I did and turn all the way to the left (counterclockwise) to achiev a neutral setting to start out with. I think this is info that ppl were most confused about.


Thanks :toast:

Here is my complete mod
http://home.attbi.com/~kamil2002/DSC00181.JPG

http://home.attbi.com/~kamil2002/DSC00182.JPG

All works well. I am now running 210mhz rock solid at 1.74vdd. It is red in the boot up health but i don't think that matters.

Alright here it is step by step:
1. First you need your materials: i used this pot from radioshack http://www.radioshack.com/product.as...Fid=271%2D342, you also need either smd grabbers (which you can't get locally at radioshack) or tools for soldering, and finally a heavy gauge wire (ie battery leads but it really can be anything). Also I would HIGHLY suggest getting a digital multimeter so you know exactly how much resistance you are giving the voltage regulator before you start it up the first time.
2. Once you have your tools in order you need to set up your pot. The wire that you will solder to PIN 1 will be attached to the MIDDLE pin of pot. The grounding wire that you will solder to pin 4 OR any ground (ie case) will be attached to one of the other pins on the pot. So now you should have two wires, both of which are soldered onto the pot, one in the middle and one on one of the ends.
3. At this point i would test the pot and set it for your desired setting. About 740~750 Ohms should give you about 1.8 v for the chipset. So take your multimeter and measure from one wire to the next (making sure to have it set on OHMS first). In order to adjust that little knob get a mini screwdriver or a razor and turn it while measuring either clockwise or counter-clockwise to get your desired resistance.
4. Once you have the resistnace dialed in its now time to do the actual mod. I would suggest against using smd grabbers as in my limited experience they are very hard to use and will not stay on and if you really want to, you can always take off the mod by heating up the solder and pulling it off. Anyways onto the mod. The chip you are looking for on your board is labeled, IOR 3037A. It is located between the first dimm slot and the nb and will have a large coil just south of it and one to the left. Here is a pic for a more visual representation: .
Ok now we have found where we are going to attach the mod. The first pin counting from left to right is where we want to attach the wire from the MIDDLE pin on our pot. At this point you can either solder or using an smd grabber. If your going to try soldering, i would suggest going very slowly as the pin is very small and very close to other pins that you could short out by soldering. Don't panic though if you do get solder on lets say the 2nd pin just heat the solder up with your iron and try and move it over/clean it up with something disposable (ie paper tower or tissues). Moving on, the ground wire, the wire attached to one of the ends of your pot now should be attached to either pin 4 or to any part of your case. Personally i attached my ground to the case by use of a screw (ie you unscrew it a little bit, shove the bare end of the wire into the gap and screw down till tight).
5. At this point the mod is essentially done. Here now are a few pics of the finished mod just to give you guys an idea: and another pic here:

That does it for the mod. All thats left now is to turn on your computer and let her rip with those high fsb's! Hope this little guide helps any newbs out there like me. And btw if you ever feel like adjusting your vdd voltage again its as simple as turning the nob on your pot but be careful to do it slowly. On a pot like the one i have above this is not so much of an issue but still don't just go blindly turning without abandon.

edit -- eh whoops the pics aren't workign so i had to remove them. You can get the pics i was using over at http://www.hardforum.com/showthread....5&pagenumber=1 . Scroll down and you will see the pics of the finished mod.:banana:

the pic u linked to shows the left pin being connected to the outer pot leg and the right pin connected to the middle !?!?! I have everything to mod i just need verification that i will use the correct pins. Also how should i turn the pot to attain no v change. I want to start out with a neutral setting and then increase voltage.

You can do it the way in the pic, its just you can not attach the wires at either end. In order to attain a neutral setting you will have to measure the resistance. For simplicity's sake just make sure the pot is set to 1k ohm when you put it in your comp. AFter that you can adjust it accordingly.

I did the mod. My first soldering job ever and it worked!!!! I will not get a multimeter so can I use the setting it came at. Is there a rule such as all the way to the right or left will give me 1kohm? I don't want to dish out the money for a meter just for this mod.

Thanx =)

Turn it clockwise as much as you can and you should be fine as this increases the resistance. The only way you can be 100% sure is with a mulitmeter but turning it clockwise should be effective. Once you start it up the first time you can then turn it down and watch you voltage change in bios.

Thanx Professor. It seems ur the all knowing in this thread LOL. Hopefully I will boot it up today. I need gaskets for my swiftech pelt before satrat. I will also mod my r9700 since i kinda like this new soldering skill i just picked up. Its really fun. On to mod everything in my puter. heheh

I picked up a multimeter from RS and i am trying to set my resistor. I set the meter to the 2k range and I get a reading of 0.072 does this mean 720ohms or is this actually 72ohms. If i turn left or counterclockwise the number goes up. This doesn't make sense as u said that all the way to the right is the highest resistance. So what should my LCD display if I want lets say 720ohms ~1.85v right?

I am almost sure that 0.072 means 72ohms.... When i desoldered the pot from the board it read .268 i set it to .780 and found the max to be 1.032. That makes sense its a 1k pot. Here is a new question. Should the resistance change after i solder the pot to the board. If so all is good if not then i must have fugered up on soldering to pins 1 and 4. I hope it is meant to change when connected. Pls anwer asap if u can.
:toast:

hmmm thats odd but it depends on where you were trying to measuer it after you put it on. YOur reading before of .720 is accurate and you should base it off that unless you somehow cut the wire or possibly got too much solder on? I am really not sure why the reading would change but as long as you set it before you solder it on it should be ok.

Do u think the mod is done good? Can u check if urs shows the correct resistance at the pins?

Hey just a quick question, will a fixed 730Ohms resistor be ok to use with this mod? That should be enough volts but not too much right?


Cheers :D

Yeah that should give you 1.84ish depending on what your initial voltage was.

On my pot, when I use the left and middle pin I have to turn it all couterclockwise to get 1K, and when I use the right and middle pin I have to turn it all clockwise... Isn't this the case with all pots?

I wouldn't risk using it without a multimeter, it is set the wrong way (close to 0 Ohm) you'll give a LOT of voltage to the NB I'm afraid...

Quote:

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wouldn't risk using it without a multimeter, it is set the wrong way (close to 0 Ohm) you'll give a LOT of voltage to the NB I'm afraid...

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This is why using a fixed resistor is a wise move instead :D

Yeah thats how i think it. From what i have read a pot works by moving resistance on the pins from one end to the other. So one end will be at 1k ohms and the other at 0. Then as you turn the pot they equalize and it shifts the other, sorta a slider effect.

I can verify that as turning to the right gave me almost 0ohms so without the multi i would be really screwed. Any word on measuring resistance with the pot soldered to the board. I'm really iffy about booting up my board, but i have time couse i have to wait for parts.

Did i screw up the mod.

Well like i asked before where are you measuring the voltage for this? As long as you measured the resistance through the wires before you put it on and it was good then, I see no reason why there should be any discrepancy before or after. Perhaps someonelse may be able to help?

is it safe to turn while its hot?

Supa MAn: YES

I did test befor and set it accordingle. Just worried that it gives me different reading when soldered to the mobo. Oh well i'll live with it.

Quote:

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Originally posted by Professor12
Turn it clockwise as much as you can and you should be fine as this increases the resistance. The only way you can be 100% sure is with a mulitmeter but turning it clockwise should be effective. Once you start it up the first time you can then turn it down and watch you voltage change in bios.

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You're lucky he got a multimeter and didn't listen to you, he would have smoked his board! :eek: :eek: :eek: :rolleyes:

If you turn the pot all the way clockwise then you will see the full resistance of the pot between the middle pin and one of the outer pins (safe). The other pin will be a DEAD SHORT (0 OHMS!) to the middle pin, which is the way he had it hooked up at first (transistor BBQ). :eek:

The resistance on the pot reads differently after it's connected to the board because you are reading not just the resistance of the pot but also resistance (and capacitance) of the mobo circuit connected in parallel to the pot. If you don't change the pot and disconnect one of the wires, you'll see the same reading you had before you installed it. All normal.

Thanx for confirmtion i posted pics up above

Nice job PJ!

You might want to put some electrical tape on those bare connections (and the live unused pin) on the pot, that's what I do. It would suck to have a connection touch something it shouldn't (like back of vid card).

Quote:

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Originally posted by Spartacus
Nice job PJ!

You might want to put some electrical tape on those bare connections (and the live unused pin) on the pot, that's what I do. It would suck to have a connection touch something it shouldn't (like back of vid card).

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Speaking of my vid card check this out here :banana: :banana:

Sticky?

what kind of soldering iron do I need? I saw a 30 watt one I thought of picking up. It is a straight jobber not shaped like a gun. Is this ok to use? Also what kind of solder do I need? I saw some really thin kind. Can you reccomend the right size? Also where can I get those wires. When at Rat Shack I looked for 9volt battery leads but they had none. Is any wire ok? What gauge is correct?

Also I had picked up a micro size 1k pot
Is this ok to use, Or should I just return it to get the 1k 15 turn?

I am really sorry for all these questions.

I really appreciate anyone who takes the time to answer these questions!

Couldn't figure I am a noob when it comes to v-mod's huh?

I just fried my asus today trying to do a the vddmod.....needless to say I dont wanna fry anything again. Im picking up a 8RDA+ on monday and would like to verify what I need to do. Is this correct way to get 1.85v:


pin1---------------720ohm resistor--------------ground

Ill be using a smd grabber to pin1. or

pin1-smdgrabber------------720ohm------------smdgrabber-pin4

This should work right? which would you guys recommend... thx

That would work yes, it certaintly shouldn't fry anyway. Personally I would go with the pin 1&4 combination.

LikwidKool:
I got the soldering iron kit at the shack with the solder already in the box. I believe its the one u are talking about. Just a straight stick 30wats. It takes about 3min befor ready but gets the job done. There is no solder size couse u melt it on to the wire and then put the wire in place and touch it with the iron to get it to melt over the correct pin.

Alright I get it. I just thought I bigger piece of solder would create more mess, therefore a smaller gauge would be more trouble free.

Thanks for the reply. I hope mine comes out as good as oyurs. My board get's here tommorow. Wondering if I should do the mod before I even install it or see how it runs first. Hell, who am I kidding. Mod it first!!

I just had to comment on this, I recently picked up a 8RDA+ and probably will to this mod later on down the road. I keep seeing questions come up about the resistor...variable, fixed, death, which way do I turn the pot the list goes on. Not once have I seen anyone post anything about using a fixed resistor in series with a variable. It's Ohm's Law, you should know it before you even pick up a soldering iron. If you find out what resistance lets say 580 ohms runs you at 2.0, thats realy high and may not be correct figure but I will use it as a example. Now if you where to attach a .5k (or a lower value) variable in series to the the 580 ohm fixed you will now have fail safed your mod. The fixed will not let you go above a set voltage and the variable will alow to to trim down the voltage to what ever you desired. Now you wont have to worry about overvolting the board beyond the fixed resistor values. Just my suggestion if you still want the room to turn it up or down.

I found that the radio shack resistor (1k) is by far not sensitive. I had to turn and turn to see the volts rise. Safety is not a problem with the one i used couse u just can't accidently go too high if u are sober.

To be honest with u i learned about resistors from doing this vdd and i still have no idea how to calculate resulting vdd. I;m a complete newb in this stuff but i just know how to make it work safely thanx to the help i got from XS.

hey guys... well mainly professor but that link to RS doesnt work

Yeah sorry for the broken link. The pot is not sensitive enough? Its a 15 turn pot and the idea is that it is not sensitive so you don't kill your §§§§ by turning it too fast. Perhaps someone can give you a link to calculate voltage but i know there are some sites or you can calculate it yourself (though i don't know either off hand).

well, VDD mod a sucess, I wilol post pics and thoughts later.

Prof, I copied and pasted your guide into another forum where ppl were asking how

I gave you FULL credit for the guide. I will supply you with the url if you wish? Also if you want me to take it down. I will too. :)

Lol i have no problem with anyone posting this mini guide. Oh and btw what was the link? I'd be interested to see how people are faring with it.

the site has been down for a few days, when it goes back up, I will let u know :)

Thanks guys.Vdd sitting at 1.8 after following the guide in the thread.Was a bit concerned that I screwed it as my soldering iron's head was a bit big,but up and running at 200x12 . 184x12.5 was the highest I could get stable before the mod.Removed the nb heatsink,AS3'd it and stuck a 60mm fan on top just in case.

Damm,just realised I forgot the fit the mosfet heatsinks.....:slobber:

Thanks again :banana:

Prof, here it is.

http://www.bigfootcomputers.com/cgi-bin/yabb/YaBB.cgi?

board=hardware;action=display;num=1044540173;start =

bump i know some guys will need this guide lol... the question pops up everywhere

well I screwed my first try. I got a blob of solder on all the legs and didn't get it all out. I thought it was good and tried to start the board, but just the fans spun. No POST led or POST beep. I took it back out and just kept heating and moving, and it all cleared up and looks like new.(sorta) She started back up with no problems whatsoever. I have another day off tommorow so hopefully I will have the time to try again. I am prepared this time with a desoldering squeeze bulb, and some desoldering thread:)

So I took another crack at it today, and it's VDD Goodness! Have it set to 1.76 vdd right now for starters. Already working because 200fsb would give me the flicker and right now it is solidly stable!

BTW just to clarify cause I did it wrong first and it wasn't really clear:

On the pot the hot wire is either side, and the ground is the middle leg. Also on the chip itself, pin 1(hot) is on the left and pin 4(ground) is on the right if you were looking at the chip head on. As per what I had read, and the pics I saw, I reversed everything and when I booted at first and didn't see a change I got worried. Then I searched through a bunch of threads and found the right info. Funny that all the pics I saw have the black wire on pin1 and the red on pin4, which normally red is hot and black is ground.

Thanks for the help guy's. I owe you one!

a couple questions before I do this...if I get the adjustable pot do I still need to get a resistor? what ohms should I set it at if I want about 1.9vdd (i'm going to have a waterblock on the northbridge so i'm not concerned about the heat)? Where and how did you attach the pot to your mobo, all the pics i've seen just had it sitting there out of case. So if I don't need the resistor, is all I need the pot, and battery wires? Which pot to get the 1k or 10k?

mine is using a 10k 15 turn cermet pot . That is all I was able to get from Rat Shack. I believe though the one to get is the 1k 15 turn. It just took a while of turning to get it all the way down. I set it at 1k and then adjusted it per the bios reading for vdd. I have heard to turn slow, and wait a little after to let the change settle.
My pot is just hanging there at the bottom of the case on the little plastic drive rails.

LikwidKool: I made an update for ur question on cable placemen on the vr. I was also confused when doing it the first time.

EDIT: Sorry link LOL i just glanced at ur name. Man I was way off :toast:

Thanks PimpJack. That should make it a little easier for others.

BTW it is LikwidKool, not Linkwood. That is the second time. 3 strikes you are out!:DLoL!(totally kidding, need to clarify because you can't see the big smile on my face!:D)

Hey guy obviously I don exactly understand why r u doin a Mod like this. From reading thru BIOS monitoring Vdd is the AGP voltage. But from all the thread I read it seams it's VCORE the ones being discussed? I'm right? Sory 4 being so ignorant. 1 more thing there's a 1.90 VCORE in BIOS right? Why not use it?

If so is it really safe if I do it right? Choices of POT or fixed resistor?
Anyway not to have V mods for high speeds?

THANKS!

vdd in bios health section is the chipset voltage. There is no vagp reading and u can also see a vcore (cpu) and vdim (memory)

I would use a variable so u can increase/decrease ur voltage. And no the vdd )chipsetvoltage) is not adjustable on the 8rda's thats why we have the vdd mod.

Also a *bump* for Rudzer (i hope I got ur name right LOL)

Hi all, I'm thinking of using a fixed resistor instead of a pot. It is like what I did on my 8KHA+ (using 200K Ohm resistor for Vmod)

Can someone please let me know and correct me if I am wrong, a 720 Ohm resistor will get you around 1.7-1.8 VDD

Therefore if I get a resistor of a lower value, 600 Ohm for example, will allow me to get a higher VDD (perhaps 2.0 VDD) ?

Thanks and if possible, please suggest to me what resistor I should use, 720Ohms ?