get more vcore under load: vdroop pencil mod (pics)

[graysky]

This is one of the easiest mods you can do to your P5B-Deluxe (and probably any P5B although I haven't tested it on any model but the Deluxe) to help you get higher voltages under load conditions and also lower your idle vcore; it is particularly useful for people wanting to get more juice to feed their o/c'ed chip.

Background
As you know, the P5B-Deluxe (and others in the P5B family) has a vdroop built in for some reason (protect processor maybe, I dunno). Vdroop is the term used to describe the voltage drop between idle and load conditions.

Try it yourself right now: (assuming you have your vcore manually set in your BIOS) load up CPU-Z and see what it's reporting as your idle vcore. Now load up a few instances of orthos and have a look. For example, before the mod, mine dropped from 1.280v (idle) to 1.232v (load) which is -0.048v! After you do the "pencil mod" it should drop by a very small amount or none.

The "Pencil" Mod

What do you need? A soft pencil. Look for one with a 2B rating on it. Standard pencils are HB. HB pencils will work, but the softer the pencil lead, the better the results. You can find a 2B pencil at most any office supply store (staples, officemax, etc.); they are usually in the art or drafting section (aisle #7 for my staples). I got one in 4 pack for under $3.

Now, either unplug or switch off your power supply so the LED has gone out and simply shade (gently draw with the pencil back and forth) over the correct surface mount component (it's a resistor maybe?) -- refer to the pictures below... it's the one with the yellow arrow pointing to it.



You can see on the zoom where I colored over the right one.

NOW, boot into Windows and repeat that exercise where you measure the load and idle vcore. Mine went from a drop of 0.048v before I did the mod to a drop of 0.008v after the mod. These are both @ a BIOS vcore of 1.3250v.

I recently lowered the BIOS vcore to 1.2625v and now I have NO vdroop at all: idle is 1.232v and load is 1.232v, and the system is stable to 2x orthos for over 6 h!

Undoing the "Pencil" Mod

You can undo this very easily with a little alcohol and a few q-tips. It is 100 % reversible.

If you found this useful, please post your before/after results in this thread.

Enjoy!

[d44ve]

An already very well known mod... but very good on the pictures and clearing up the actuall mod part itself.

Very nice

[Sasqui]

I went through a P5B-Dlx and returned it because of the Vdroop - I NEVER thought it was intentional! My DQ6 does the same thing when voltage is anything but stock and EIST is disabled, but not to the extent of the P5B. I like the DQ6 more mostly because of the bios - I wonder if there is a mod for that... good write up - that certainly looks like a resistor and how much pencil did you use?

Like to see your sys specs. Cheers

[graysky]

@Sasqui - I shaded across it for about 20 seconds, maybe 20-30 stokes. Sorry, I didn't realize I had to enable the system specs. It's on now.

[Sasqui]

thx - OT, I got a big boost by dropping my E6600 multi to 8x and setting the RAM divider to 1:1. That put the FSB to ~400, so the DDR2-800 is running near/above spec. The most efficient RAM dividers are 1:1 and 1:2 - at least on the 965 chipset. Many banchmarks out there to confirm. If your feeling adventurous give it a try.

[DOM]

I want to but im Scared

[Urlyin]

graysky you should post the ohms of the resistor reading before the mod and what it should be to obtain a safe mod ... to much graphite could cause issues, just to remind people ... also pencil mods degrade over time as the graphite either gets blown off from fans or rubbed off...

[graysky]

Originally Posted by DOM_ATI_X800XL_PCI-E

I want to but im Scared

Give it a try dude... sometimes you gotta take risks in life If you're thinking stray graphite may get on the board, just hit it with a puff of compressed air after you're finished.

[DOM]

Cuz in my bios its set at 1.5v but in window its 1.45v and right now its folding and speedfan says 1.45 and cpu-z is showing 1.448v is that any good ?

[graysky]

This mod will only change your idle/load vdroop. I' unaware of one that changes the BIOS/operating system vdroop: there is always a difference in the bios vcore and the windows vore from what I know.

Example: my system is set to 1.2625v in the BIOS, but idle/load is 1.232v or about 31 mV difference. What is your idle/load vdroop?

[DOM]

Originally Posted by graysky

This mod will only change your idle/load vdroop. I' unaware of one that changes the BIOS/operating system vdroop: there is always a difference in the bios vcore and the windows vore from what I know.

Example: my system is set to 1.2625v in the BIOS, but idle/load is 1.232v or about 31 mV difference. What is your idle/load vdroop?

Idle/Load 1.46v/1.432v Load with orthos small FFT test

[graysky]

Originally Posted by DOM_ATI_X800XL_PCI-E

Idle/Load 1.46v/1.432v Load with orthos small FFT test

Did you do the pencil mod or is this stock?

[graysky]

Just the hell of it, I dropped my system back down to stock 9x266 to see how low the vcore could go and still run stable. I'm at the lowest value in the BIOS (1.1000v) and it's been stable to 2x orthos for ~1h now (still going).



Anyway, no vdroop at this setting either. 2B pencils rock for this sort of modification.

[DOM]

Originally Posted by graysky

Did you do the pencil mod or is this stock?

Stock

[graysky]

Git it a try dude. Come on, everybody's doing it

[DOM]

Originally Posted by graysky

Git it a try dude. Come on, everybody's doing it

But what is this going to help im stable with my OC

[graysky]

Only thing it'll buy you if you're not voltage limited is a cooler idle temp.

[DOM]

Okay I want to try this now

Where can I get a good Pencil ?

I live in a good size town 200,000+ so theres staples, officemax, etc.

Or is there one online that would be better ?

[Mediocre]

Staples

all they had at office max was 'medium-soft' which is probably more difficult to work with.

I used a 0.5mm Pentel#2b 'refill' for a mech. pencil

EDIT: That pencil looks like the pic is a #2HB, not what we're looking for. Might be a default photo though...

Anyway, if you're in a school (or know anyone in art or drafting), you can find one there

If you work in an office, everyone has an 'old' pencil collection, rummage through that.
These types were widely used 20yrs ago when they did drafting by hand (sorry not sure if you're old enuf to remember those day...I actually drafted with pencils in school ).

[DOM]

im only 22

Well where did you get yours from ?

[Mediocre]

Originally Posted by DOM_ATI_X800XL_PCI-E

im only 22

Well where did you get yours from ?

Cabinet at work. We used to have a drafting department in the late 80's

An art store would carry it...maybe swing by your parents/grandparents and check there. You might even have one labeled as #2, you'll notice when you use it, it lays down a darker stroke than an 'SAT Approved' pencil

[Kursah]

I did this mod on my first P5B, it worked as described, and my current P5B setup does have the same vdroop. I plan to do it again, just haven't gotten around to it. With my vCore set at 1.40, I get 1.36 idle, and 1.34 load, which keeps me stable at 3.5 (500fsb). So I may want to try this out and see if I can drop my vcore a tad.

Good post, I dig the pictures, some of the best I've seen for this mod.

[p_o_s_pc]

it is funny how my board gets higher v-core underload when OCed.Maybe it is something to help keep it stable.

[DOM]

Originally Posted by Mediocre

Cabinet at work. We used to have a drafting department in the late 80's

An art store would carry it...maybe swing by your parents/grandparents and check there. You might even have one labeled as #2, you'll notice when you use it, it lays down a darker stroke than an 'SAT Approved' pencil

parents/grandparents they dont live here im alone with my dogs and wife shes the only one that has family here

what about this

[Mediocre]

nope, thats hard lead

check here scroll about halfway down, the 'very soft' 2B refills...

FYI I didn't even have a mech pencil to put it in...I used an alligator clip