Proth's P5WD2 Vdroop Ghetto MOD

This mod is for those timid or over caffienated people that don't want to take a soldering gun to your mobo. This is no joke and works quite well. The goal is to lower the resistance of the Analog Devices droop circuitry from about 75k to 40k ohms. The PIC below has a "proper" vdroop mod, so please ignore the wires and pot which isn't required. Should be able to do this mod without removing the mobo.

Sharpen a #2 or any other soft lead pencil really sharp. Jam the tip of the pencil between Pins 17 and 18 of the Buck Boost converter/regulator. Rotate the pencil while applying slight downward pressure, then snap off tip of lead so it remains jammed between the pins. Low risk, should keep droop under 20 millivolts: Maybe FUGGER can make a GHETTO section, cause I have a lot of ideas on cooling and cases.
http://img348.imageshack.us/img348/6...ettomod9tn.jpg

Thanks for this easy mod! I' ve just done it, works fine...

http://img87.imageshack.us/img87/1724/ghetto8js.jpg

Nice mod! Beatiful actually since it´ll probably get someone to try ghetto.

I´m so addicted to this, it´s like the freeride category of modding. Just you and the hw and stuff not ment to go inside a computer. Not just replacing stuff with better preforming parts and (carefully...) putting together again. Ghetto is so underestimated... It´s the real deal.

Quote:

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Originally Posted by proth

Maybe FUGGER can make a GHETTO section, cause I have a lot of ideas on cooling and cases.

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Go ghettosection now! And proth: keep up the good work!

You could then add a drop of nail polish as well.

:toast:

awsome, works wonders for my 930, which is much worse than my old 920.

This worked great for me till I replaced with the VR. :D

After doing the pencil mod what should the resitance between 17 and 18 be??? mine is 1.4kOhm isnt that a little low? Dont wanna power it up until i know.
I)ickie
p.s. this is with a p5nd2-SLI but it has the same ADP3181 so i assume it works the same

so thios WILL NOT work for a regular old P5WD2?


EDIT: YES it will

Quote:

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Originally Posted by n00b 0f l337

You could then add a drop of nail polish as well.

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I guess it would lower the resistance too much . Right ?

It works on my p5nd2-SLI great. Just need a board with the adp3181. Of course the points for soldering might be diff. Correct me if im wrongt but you just need points with 0 resistance to pins 17 and 18. The pencil mod should still be the same. But check resistance before you boot because i had to do a fair bit of fiddling to get resistance between 20 and 30.
I)ickie

Just to add to the list. I did this pencil vdroop mod on my P5WD2-Pre and P5LD2 both of which has the adp3181 buck controller. No vdroop in any of those mobos now. But my vcore now is set at least .1v higher than whats set in the bios. But thats no problem. I just reduced the vcore at the bios and both machines are happy campers now.

Quote:

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Originally Posted by greenwar

But my vcore now is set at least .1v higher than whats set in the bios.

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It happens with hardmods and ghetto mods :p:

sorry to ask this here, is there a pencil mod for the P4C800-E
im getting up to 0.07v droop and its killing my overclocking.

my P5WD2-E Prem does the same :banana::banana::banana::banana: so i plan on doing the pencil mod to that, thats for sure!


one thing to remember guys is that pencil led when used for certain things such as this doesnt last forever. i mean i doubt it would degrade fast enough for any of us to see it happen but i just throw that out there for anyone who wants to know.
i have yet to see a properly done pencil mod go bad but it can happen.

Quote:

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Originally Posted by Lestat

one thing to remember guys is that pencil led when used for certain things such as this doesnt last forever. i mean i doubt it would degrade fast enough for any of us to see it happen but i just throw that out there for anyone who wants to know.
i have yet to see a properly done pencil mod go bad but it can happen.

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I agree but the good thing about a pencil mod like this is its not gonna kill anything if it does.

I)ickie

i have some pencils here but i cant tell if they are #2.

i put my DMM on OHM's and put the lead on in between the positive and negative leads of the DMM. the DMM then reads 0.02......
is this about right or should a #2 pencil read ????


someone do that and tell me.

i mean thats my understanding of checking for ohms. turn the DMM to the ohm setting and test whatever your testing. i know when i touch the + and - keads of the DMM together WITHOUT the lead between them the reading was way way higher, so i figure the lead is offering resistance. and 0.02 Ohm of resistance.

am i correct on this ?

sorry electrical stuff has always been a weakness of mine.

That pencil should work fine. The P4C800 uses a different chip so the pencil mod will not work on it. My kid runs the P4C800 and it's been modded with a resistor, fixed the droop big time. There are a lot of PICS around on how to do this.

proth i sent you a pm about what we talked about before

hey this whole pencil mod actually reverses the droop.
meaning

now instead of drooping the vcore INCREASES..... uhhh.... i'm not sure i understand how or why ?

idle its nice and steady though.

i was unable to actually break off the lead between the pins though cuz they are so close together so i just did the best i could.

not to mention the vcore is now 0.10v higher than what i set in the bios.
the bios is 1.35 the vcore in windows with every application i can find says its 1.45v or a little higher.

here are some pics

I have a quick question about voltage readings. I measured my volts from the mosfet to the ground and got 1.25idle/ 1.15 load, but windows reads 1.45 solid. This is on a vdrooped P5WD2-P and P4 630 set to 1.37 in bios. Is that mosfet reading to far off? If so, then why? I just got done modding this board so I'm testing everything out.

might be a silly question ,but where does one buy these lead pencils from?anyone wonna send me a small piece off one :D and nice finding there proth.

Quote:

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Originally Posted by Lestat

proth i sent you a pm about what we talked about before

hey this whole pencil mod actually reverses the droop.
meaning

now instead of drooping the vcore INCREASES..... uhhh.... i'm not sure i understand how or why ?

idle its nice and steady though.

i was unable to actually break off the lead between the pins though cuz they are so close together so i just did the best i could.

not to mention the vcore is now 0.10v higher than what i set in the bios.
the bios is 1.35 the vcore in windows with every application i can find says its 1.45v or a little higher.

here are some pics

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I am experiencing the same thing, instead of dropping, it actually rises.

Quote:

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Originally Posted by vanovich

might be a silly question ,but where does one buy these lead pencils from?anyone wonna send me a small piece off one :D and nice finding there proth.

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any pencil will work. The graphite in the pencil conducts electricity :toast:

i tried it with the pencil and got some wird results. the voltage opped like0,1 from what i gave it .the drop under load is much better now .lets say im 1,4 in biose .probe shows 1.5 then when i load the cpu it goes to 1,52 which is ok .the thing is ,that befor ,the pc was stable at 5,2 mhz ,and now im barely stable at 5,1 . wierd wouldnt you say .

I dont know yet, but I think it works on P5P800 Se to, I had big drops and now les with the mod... I tried this because the P5P800 Se has the same IC number.

weird vanovich... Thats why I wont make the mod:)

This worked a little to well for me, i have a pentium d805 and under load it would go from 1.60 ( selected in bios ) to 1.32.
But now it does this; i set it to 1.6 in bios and under load it goes up to 1,75

Quote:

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Originally Posted by LyP0

This worked a little to well for me, i have a pentium d805 and under load it would go from 1.60 ( selected in bios ) to 1.32.
But now it does this; i set it to 1.6 in bios and under load it goes up to 1,75

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did you do the pencil mod? If so check your resistances. You only want a resistance of between 20 and 30. I have found that 25 works very well for me.
I)ickie

yes i did the pencil mod, i dont mind... think its ok.
first i wasnt able to do 3300 stable now i'm doin 3900.
one thing still bugs me, my bios says 1,7
cpu-z shows 1,7
everest tell's me its 1,45
to be honest i believe everest. I'm running on air cooling and temps are max 67 deg. not lapped cpu. I dont think the vcore is right in cpu-z and bios, because i know other people wo are doing 3.6 or so and have a temp of 75-78 with same cooler and 1.5 volts

you would believe freaking everst over cpu-z ? yeah uh huh.. sure..

67deg ? your gunna kill that cpu.
and if you saw others running 75-78deg then they are ,,, well i wont say retarded but thats what i want to say and so are you if you think those temps are ok.

your gunna shorten its lifespan if you keep running at those temps.
and you may be seeing some thermal throttling going on at those temps.

if your bios says 1.7 then thats what it is
and god help you if your running 1.7v on that cpu on this motherboard.

yes the Pencil mod reverses the droop so now its not a droop its a *insert funny phrase for a reverse droop* its an increase.. and once again your running 1.6v on that cpu your nuts especially on air

i wont even go over 1.5 and im on water

need to lap this cpu, mayby it would give some better temps. but a'm not verry concerned about the lifespan. i'm going to get a conroe when they come out and a celeron d 356 in a week or 2.

btw if i go back to 3,0 ghz and set my vcore to auto i get 1.5 volts and 65 deg.

btw 2 , i should probably tell you my room temp is currently 38 deg ( live on attic next to dry'er,washing machine and tanning bed )

AARRGG Fowers in The Attic!!!

so how the hell do you get above 1.5v with this mod.. its really pissing me off and limiting my overclock.
i only need 1.42 to run 4.5ghz stable but i cant get any higher unless i hi 1.5v and i cant with the pencil mod. the system wont even boot with 1.5v
i had it higher than that prior to the pencil mod. so i know its the pencil mod doing it.

the way i did it was like this :

------------------
| | |==| |

i tried to drew small ( miniscul ) lines between the two pins, you cant actualy see, you have to do it using one of these

huh ? were you replying to someone else as i didnt ask how to do it i asked how to get past 1.5v the mobo wont let me. it just bombs if i try

im gunna pull this all apart this week and send it to proth to mod so im not all that worried but if i can get away with NOT destroying the warranty i would prefer that.

Quote:

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Originally Posted by cronic

I am experiencing the same thing, instead of dropping, it actually rises.

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The resistance has been lowered too much... This is why it's best to use a VR if you have good enough soldiering skills. ;)

no soldering skills here not for things that small. i have to use a magnifying lense just to properly see the chip to do the pencil mod

well i have done the pencil mod.

i have got 0,1V incresement.

my 940 Presler runs at 290FSB 4640Mhz Stable with watercooling
but i want to reach the 300FSB or more.
actual settings:
VChip 1,6V (PCI-E)
Vcore 1,3V (1,4v measured)
VMem 2,1V (don't need more bcz of hot chips)

P5WD2
G.SKill 5400 GBHZ
940

any tipps?
can someone give me information for incresements ?

thats very low volts you need to raise the vcore.
everything else seems ok

whats your FSB speed ? like 1160 ?

Quote:

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Originally Posted by Lestat

thats very low volts you need to raise the vcore.
everything else seems ok

whats your FSB speed ? like 1160 ?

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ok
i got it. 305FSB 4880 Mhz . but 1,5V (measured)
and hot like ... 50°C idle with watercooling (only cpu and NB cooled)
load up to 75°C

well and it's seems to trottle bcz of overheating
so i'll select 4,5Ghz with 1,325V (measured)

Is there also any non-hardmod to get more vdimm in the mem's on a P5WD2 Premium ?

only possibility would be to do a direct wire from the 3.3v line to the vdimm which would lock your vdimm at 3.3v and kill any ram you tried.

i dont know why you need more vdimm. this board gives enough vdimm for all but one type of ram that can handle high voltages.
other than that you'll just kill your ram.

Lestat, 2.3v is not enough ;)

lol

its a hardware mod only bro.

yes. I only wanted to know if there was a possibility of doing that mod in some easy way like the pencil vdroop mod ;)

I just did this mod...works like a charm! Some weird things happened though. I couldn't get the tip of the pencil to stay in between the pin points, so I kinda just rubbed it in. The voltage is now completely stable, and it actually reports about .11v above what's set in the BIOS. I don't mind it though since the voltage report is stable!

see if you can go over 1.5v
whatever setting in the bios you need to use just try to go over 1.5v real voltage.

mine wouldnt boot or it would reboot if i went over 1.5v
its like its too much voltage and the pencil mod causes it to fail

Ive tried this mod more then half a dozen times and not really had great sucess so far.

It could be because my system is less then perfect but Iam testing it after reapplying the mod, cpu, thermal compound and some light lapping on the IHS.
Seems to be better this time but Iam not that hopefully really :/

So far, winrar benchmark is almost a flatline on vcore but it just blipped from 1.39 to 1.41. 1.3375 in bios is set

S+M is the ultimate test and that switched my pc off in the past. My zalman heatsink has no heatpipes so I know that is lacking, at 2.72ghz Iam getting 61c. It throttles at 65.

If I get sucess, I will update with speedfan vcore graph.


edit:
Nope it crashed after I closed winrar and temperatures were falling. The northbridge heatsink gets hotter then the CPU one despite me placing 3 small fans around it, should I try reseating it ? If it was bad contact then surely it would not be getting hot!

The vcore does not fall from 1.39 even though the bios is set to 1.3250v now.

thats WAY!! to hot man your hurting that cpu.

go spend the money on an XP-90 or a Big Typhoon.
those are the only ones that i know of that cool it good enough.

and whats the problem with the droop mod.
it does exactly what it is supposed to do,
i stops the droop mostly and reverses it into an increase.

it obviously is supposed to do something else from what your thinking and its not. if you want the proper mod then do the hardware mod or have someone from here do it.

its called a ghetto mod for a reason, it has issues but it still works.

I found the crash was caused by corrupt software (I think) from previous crashes so Iam retesting.

I know its too hot but at 60c it should still be stable as it has been in the past with no mod. (Its idling 35c presently)

Iam not complaining just pointing out difficulities Iam having that others might too, its a budget system which is why I appreciate the ghetto mod but I cant upgrade the HSF quite yet as I just brought some ram

I havent found any vcore increase under load yet but it is looking a bit more stable now so I'll continue testing and report any sucess I get.
edit: froze again after dual sp2004 had been stopped when trying to load another program
Giving up for now as its more unstable with the mod then without, I'll try again once I find a proper 2H pencil

Yeah, over 1.5v is no problem. I have my 805 at 3.9ghz 1.6v now...70C load under AS Ceramique and BT. These things run hottt...but I know Intel's can take the heat (esspecially the 90nm ones).

From what I can see, the mod doesn't really help my overclock though. 4GHz is still unstable with the first core. I have an untested Ninja here as well...and I need to get some sandpaper to do lapping on these sinks. Maybe then I can get the big 4 before I go conroe.

Anybody know would this mod work for the Asus P5AD2-E Premium. It has the I925XE chipset.Did I understand this correctly: So I have to put a small piece of the lead between those pins or just rotate the pencil between them that they have the graphite on them? I guess it's best to put some tape on top of those pins that the graphite doesn't come off.

Just needs one of those adp8131 chips to work on your board I believe.


When I was lapping my IHS I started to get a copper colour to the edge of the chip and wasnt sure how far to continue so left it like that, maybe all the top silver colour is supposed to come off and reveal a copper colour?

Even a small lap seemed to help temperatures though :)

It is important to have the optimal Voltage on your CPU when under full load. Who cares that the Voltage goes up a little bit under less load.
The power consumption is going down dramatically under less load, so what purpose is served when reducing droop some tenth's or even less of a Volt ???
The CPU doesn't care and the power consumption is hardly affected.

Damn :( The chip on this mobo is ADP3180. But I found this quide to droop mod this mobo->

"The mod was made to the motherboard by adding a 200kΩ trimmer in between of the bases(legs/pedestals) 17 (CSSUM) and 18 (CSCOMP) of the control(/guidance) chip ADP3180.
Lesser resistance value decreases the dropping(/falling) of the voltage."

The idea seems to be the same when doing the the normal soldering mod to this mobo and with the P5WD2, so maybe it works with the pencil mod too?

The mod at the top of the thread talks about a 50k pot though and your saying 200k, Iam not sure pencil will do the job there..

I wouldnt take any chances anyway, Ive just lost a partition due to instability crashes so dont gamble anything you cant lose





Edit:
Ive managed to reverse the mod and after a reinstall it doesnt crash now but my voltage chart looks a bit weird, was playing counterstrike at the time -

http://img509.imageshack.us/img509/6908/strange7xb.jpg

Seems like it's drooping a lot. I didn't get a answer to my question so I ask again, Do I have put a small piece of graphite between those two pins on that regulator or is just the graphite enough from the twisting to do the job?

edit. Next week buying a P5WD2 and P-D 805 so it would be nice to know how to do this properly :)

775971 that is a horrible droop WOW thats like the 2nd board i had which went right back to asus the next day.

Nazu,

you dont have to break off the lead and infact thats not really possible to do.
if you get the lead too sharp then you bottom out and the lead is too skinny and wont stay inbetween the pins.
basically if you can GENTLY twist of the tip of the pencil lead then thats better but you can also rub the lead in there enough to make a connection.

what i would do is place the pencil in the pins and if you have a way of doing so, turn on the system and do some tests. see how your voltages react.
its gunna be a one handed deal, but i did it for about an hour one night.

the other thing would be to simply run the lead there until there is enough to make a connection.
this can be problematic in that its not as strong of a connection as the solid lead. and it can be harder to remove.

personally if i were you i would send the baord to one of the guys here and let them hardware mod it.
its the only way to do it properly.

Did this mod and it worked perfect. There is a slight increase under load temprarily. I didnt put a peice in between with the pencil, simply ran it between them a few times with a very fine tip, although it is possible a small piece did remain in there. Overall it is clocking much better. I have it set at 1.4V and run nicely at 3,7 so far with tight memory timings.

Did this tonight to my P5LD2-Deluxe after having weird over/undervolt problems and now everything's rock solid. I reckon I've overdone it slightly because I set it to 1.45V in BIOS and it registers as 1.528V in windows (reading off AIBooster and CPU-Z), but at least everything's stable and I can run higher clocks 24/7 now, it doesn't drop at all under load.

hello i have p5wd2 with the adp3181.will a 4b or 3b pencil be ok to do this?

i have a pentium d 930 which i run at 4050mhz(270) fsb@1.35vcore for 24/7 use.it will run at 4.4ghz(294)fsb@1.45vcore tho prime stable.

i just want to do this as it seems to make the vcore more stable and it might go to 4.4 or higher with less power.i have not been able to get it to post over 295 fsb.
this seems to me to be a pretty good board for oc'ing.
thanks for your help
__________________________________________________ ______
pentium D930@4050@1.35vcore(270 fsb)/2x512mb patriot pc2 7200@450-900/asus p5wd2/2x80gb hitachi raid 0/bfg 7600gt@645-1620/seasonic s12 430 watt/arctic freezer7 pro(cpu)/zalman vf700cu(gpu) cooling

anybody?

I dont see any reason why this wont work.
Just check the resistances. For me the best resistance was about 20k. Just check after you have penciled that the resistance is in the area of 20-30k.
I)ickie

so the resistance between the two pins should be around 20k?

thx for the reply.

It was for me mate. It was reccomended to be by proth himself. I Would put it to 30k first to be a little safer. Just to remind you my board was a p5nd2-SLI so you might get different results than me.
I)ickie

OK , i finally tried it on my P5WD2 Premium and I'm pretty happy with the results ;)
i got 0,08v increase after the mod so now its on 1,28v idle and full load it's 1.29-1.30v
Thanks Proth ;) I'm looking forward to see more "ghetto" mods ;)

does this work with the P5W DH as well?

I have an Asus P5ND2-SLI Deluxe and a Pentium D805 and a TERRIBLE VCore drop, like I boot in Bios, CPU 3.640MHz (FSB 182) with VCore @ 1.5V. Boots ok in WinXP but durring ORTHOS the VCore drops to 1.36-1.38V.

Do I need to solder anything AND do the pencil thing, or just do the pencil mod only ?

tifozif1 you need only to pencil, but first make sure that your board is using the same IC as P5WD2.

Quote:

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Originally Posted by tifozif1

I have an Asus P5ND2-SLI Deluxe and a Pentium D805 and a TERRIBLE VCore drop, like I boot in Bios, CPU 3.640MHz (FSB 182) with VCore @ 1.5V. Boots ok in WinXP but durring ORTHOS the VCore drops to 1.36-1.38V.

Do I need to solder anything AND do the pencil thing, or just do the pencil mod only ?

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now wait,, why ask about a totally different board ?
why do that ?

Quote:

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Originally Posted by Lestat

-> now wait,, why ask about a totally different board ? why do that ?

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Can you rephrase your question ? You mean that I cannot do it ?

So, what about this ? click me

[EDIT 30 mis later] : The pencil mod is working at the moment. My FIRST mod. Thank you. Set the Core Volts in BIOS to 1.4V, it is measured 1.44V in XP and drops to 1.39V under orthos. Thank you again.

pencil mod bad...

so the first try it wouldn't boot... cleaned it off was back to normal... second try booted, had no droop, and run .1-.2 high... turned it off to finish connecting fans and wouldn't boot back up... cleaned it off was back to normal... try number three... should have stopped after two but vdroop is killin my d805 and the second time did work... kinda... wouldn't boot... cleaned it of... wouldn't boot... cleaned it off... wouldn't boot... cleaned it off again... yep i think its dead...

pencil mod bad... unless i'm just stupid which is entirely possible.

Have done the mod with the pencil but nothing changed.

http://img504.imageshack.us/img504/5...samtfy9.th.jpg

Someone an idea? Watercooled D930, Mainboard-NB-Cooler changed with a new aircooler. Thats a droop of 0,1V !

Quote:

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Originally Posted by greenwar

Just to add to the list. I did this pencil vdroop mod on my P5WD2-Pre and P5LD2 both of which has the adp3181 buck controller. No vdroop in any of those mobos now. But my vcore now is set at least .1v higher than whats set in the bios. But thats no problem. I just reduced the vcore at the bios and both machines are happy campers now.

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Just wanted to say that you should be wary in regards to the P5LD2. The 2.01g revision uses an ICS954123bFLF chip instead and there's a very high chance the pins will be different.

Since I can't even find the PDF for it (ICS was taken over by IDT from what I see...) I can even begin to research the differences. Possibly someone with the right documents could have a go.

Quote:

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Originally Posted by GFORCE100

Just wanted to say that you should be wary in regards to the P5LD2. The 2.01g revision uses an ICS954123bFLF chip instead and there's a very high chance the pins will be different.

Since I can't even find the PDF for it (ICS was taken over by IDT from what I see...) I can even begin to research the differences. Possibly someone with the right documents could have a go.

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You do realize that you are talking about the clock generator, right?
What does that have to do with a VCore related mod?
If the P5LD2 really has the adp3181, like greenwar wrote, then everything is fine. He should just know that he probably totally overdid it with the resistance, if the VCore now is generally 0.1V higher than before. The point in a vdroop mod is to get rid of the voltage drop on full load and not to increase vcore. You'll probably harm your CPU through some additional voltage spikes on load changes, if you overdo it that way.

Quote:

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Originally Posted by celemine1Gig

You do realize that you are talking about the clock generator, right?
What does that have to do with a VCore related mod?
If the P5LD2 really has the adp3181, like greenwar wrote, then everything is fine. He should just know that he probably totally overdid it with the resistance, if the VCore now is generally 0.1V higher than before. The point in a vdroop mod is to get rid of the voltage drop on full load and not to increase vcore. You'll probably harm your CPU through some additional voltage spikes on load changes, if you overdo it that way.

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Oh sorry, did I look at the wrong chip? It was the only rectangular one as far as I could tell. I'll have another look.

Keep in mind there is an older and newer version of P5LD2, one that couldn't support Core 2 Duo's and one that does. It may well be Asus used a different chip on both versions. I'll have another look.

Yup I've just taken a look and on revision 2.01g of the P5LD2 there's no other similar rectangular chip. The only exception is if it's under the "Asus Fanless Design" heatsink, which is possible but then again I don't recall anyone else mentioning this. The P5WD2 also uses the same heatsink and yet the VRM chip is visible.

Strange...

Quote:

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Originally Posted by GFORCE100

Yup I've just taken a look and on revision 2.01g of the P5LD2 there's no other similar rectangular chip. The only exception is if it's under the "Asus Fanless Design" heatsink, which is possible but then again I don't recall anyone else mentioning this. The P5WD2 also uses the same heatsink and yet the VRM chip is visible.

Strange...

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What counts is not the shape of the chip (i.e. rectangular etc.), but the numbers printed ontop of it. Nearly all chips today are being produced using several package types (shapes). So, there can be different types of ADP3181s for example, that are electrically identical, but look completely different.

Quote:

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Originally Posted by celemine1Gig

What counts is not the shape of the chip (i.e. rectangular etc.), but the numbers printed ontop of it. Nearly all chips today are being produced using several package types (shapes). So, there can be different types of ADP3181s for example, that are electrically identical, but look completely different.

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Thanks. You may just be right. I'll take a closer look with a magnifying glass. I remember that on the P5WD2 it was a square chip, or maybe this was the P5W DH Deluxe. Either way I did the pencil mod back in 2005/2006 on whatever of two boards I had then.

I found a large close-up of revision 2.01g at the link at http://www.nix.ru/autocatalog/mother.../54540_top.jpg

I have a feeling it's the square chip next to CPU FAN #2. Will verify shortly.

Yup. It's the square one next to CPU FAN #2 but it says ADP3198 and not ADP3181.

Now the only question is are these two models the same and only differ in the packaging or are they totally opposite in pinout (i.e. are pins #17 and #18 still the ones to pencil mod).

I can try taking a photo of it though it's going to be tricky.

According to the PDF datasheet for ADP3198 located at http://www.datasheet4u.com/download.php?id=560535

it would appear pin #17 and #18 are CSCCOMP and GND respectively.

CSCCOMP = Current Sense Compensation Point. A resistor and capacitor from this pin to CSSUM determines the gain of the current sense amplifier and the positioning loop response time.

GND = Ground. All internal biasing and the logic output signals of the device are referenced to this ground.

On the PDF datasheet for ADP3181 located at http://www.datasheet4u.com/download.php?id=516795 there's a difference in that pin #17 and #18 are CSSUM and CSCOMP respectively. GND is pin #19 on the ADP3181.

Given the above if my logic is correct, this would suggest that on the ADP3198 one should pencil in pins #16 and #17 as oppose to #17 and #18 on the ADP3181. Would like a second opinion though. My justification for this is that one should pencil in CSSUM and CSCOMP irrespective of the model of ADP chip...right?

I've uploaded some pin-out diagrams of both these chips and marked the pins I think are valid in red.

http://img693.imageshack.us/img693/1071/adp3181.png

http://img121.imageshack.us/img121/4862/adp3198.png

Just an update to say I followed my above line of contemplation and it works on the ADP3198, just the pins are different to the ADP3181.

Tested it with a rare Q650 ES CPU at 3.73GHz. Prior to the mod the Vdroop was bad going down to 1.520V, now it doesn't go down at all but up slightly from 1.616V idle to 1.624V load with the seldom spike to 1.632V.

Used a HB pencil rather than a 2B.

Thanks for your help celemine1Gig.

Your welcome. But you might want to consider redoing the mod. As I already said, you should leave a little droop. If the voltage actually increases on full load that probably isn't exactly good for your CPU. This most likely causes voltage spikes on load changes.

Quote:

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Originally Posted by celemine1Gig

Your welcome. But you might want to consider redoing the mod. As I already said, you should leave a little droop. If the voltage actually increases on full load that probably isn't exactly good for your CPU. This most likely causes voltage spikes on load changes.

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I'll redo it with a 2B pencil once I get one. The pins on the ADP3198 are smaller and closer together than on the ADP3181 so it's somewhat tricky.

Just get yourself a digital multimeter and measure the resistance between the pins. When redoing the mod you would want the resistance to be a bit higher than it is now. ;)

Quote:

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Originally Posted by celemine1Gig

Just get yourself a digital multimeter and measure the resistance between the pins. When redoing the mod you would want the resistance to be a bit higher than it is now. ;)

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Thanks again. Will investigate the matter. Oh how I love small pins :)