How to volt mod IC7 Vmem

[[SLC]Tachyon]

Originally posted by NyCUndaGrounD
O in that case u might be screwed............... I mean even if the pads are gone there is still some kind of metal contact there in that space.

In my pic, there should be some kind of contact, if not how would the board get information from those contact pads.

There's NOTHING where the pad was right now- just black PCB.

We accidently had ripped up the trace when the pad went away- and I am unable to locate the end of the trace at all.

I put a few drops of conductive window defogger paint where the pad was- put one needle there and the other on the good pad- and ther was no change on the multimeter (should there be really?).

I just PM'ed the mod that found a workaround on the IS7 after he accidently destroyed his solder pads- I'm hoping that this mod will work for me also.

[tome]

Hi,

I tried this work around figured out by Tedlinde, meaning solder one wire to the fourth leg of the winbond chip and the other one to ground. Now the system starts but there is no beep and the monitor remains black. On page two of this thread there some pics that show how do it. Good luck.

tome

[[SLC]Tachyon]

Originally posted by tome
Hi,

I tried this work around figured out by Tedlinde, meaning solder one wire to the fourth leg of the winbond chip and the other one to ground. Now the system starts but there is no beep and the monitor remains black. On page two of this thread there some pics that show how do it. Good luck.

tome

Do you have a resistor on that wire?

[tome]

Originally posted by [SLC]Tachyon
Do you have a resistor on that wire?

Yes, a 1 kOhm VR. I tried with 0 Ohm and with 330 Ohm but the board stops booting as described above. Maybe I burned anything else near the R50 pads. I can send you pictures if you give your email.

tome

[[SLC]Tachyon]

Originally posted by tome
Yes, a 1 kOhm VR. I tried with 0 Ohm and with 330 Ohm but the board stops booting as described above. Maybe I burned anything else near the R50 pads. I can send you pictures if you give your email.

tome

I'd *greatly* appreciate pics- my email is Asmith9604@aol.com

[tome]

Originally posted by [SLC]Tachyon
I'd *greatly* appreciate pics- my email is Asmith9604@aol.com

Pics sent.

tome

[[SLC]Tachyon]

Originally posted by tome
Pics sent.

tome

Thanks for the pics

One more question though- is there any specific MOSFET/leg of a MOSFET that I should solder the wire too?

And to confirm once again, the setup should go:

4th Leg of the Winbond Chip ---> resistor ---> MOSFET

Right?



I've just spent at least an hour trying to get a wire onto that leg- with the combination of a shaky hand and poor eyesight I can't get it on.

I can touch the end of the wire onto the 4th leg- but I can't get it to stay. Using hot glue actually moves it over, and i know moving it over = useless mod.

How about SMD grabbers? Anyone aware if there are any small enough to grab a leg on the Winbond chip?

[tome]

4th Winbond leg -> VR resistor -> screw hole (ground) this is what a colleague did for me.

So far I did not see that small grabbers.

tome

[copyman]

Thanks man, work fine here

any volts , up to 3,2v no variations

[]'s

Copy

[Radelon]

I messed up one of my tabs when doin' this, so I used an SMD Grabber on the 4th leg of the Winbond chip and put the resistor inline and have it soldered to the ground leg of the mosfet. I used a 470ohm resistor and get a solid 2.97v at 2.8 setting in bios. So yes a grabber can be used. Took a bit of work to get it on there, but once on it's not moving.

[eva2000]

for a newbie who's never done any soldering or electronics, how hard would it for me to mod vDimm on IC7 so that

2.5v = 2.85v
2.6v = 2.95v
2.7v = 3.05v
2.8v = 3.15v

[Radelon]

eva, because of the small area you have to work with, it's very tough. It really was my first soldering job, but in the end I had to use the alternative way. But all is working so I can't complain.

I will be changing my resistor on Monday in hopes of getting 3.1v on the 2.8v setting.

[tome]

Originally posted by Radelon
I messed up one of my tabs when doin' this, so I used an SMD Grabber on the 4th leg of the Winbond chip and put the resistor inline and have it soldered to the ground leg of the mosfet. I used a 470ohm resistor and get a solid 2.97v at 2.8 setting in bios. So yes a grabber can be used. Took a bit of work to get it on there, but once on it's not moving.

@Radelon: Could you send me the part number or a pic of the SMD grabber you used? Thanks.

tome

email: tmehler@freenet.de

[Radelon]

Originally posted by tome
@Radelon: Could you send me the part number or a pic of the SMD grabber you used? Thanks.

tome

email: tmehler@freenet.de

SMD Grabber

That's the one I have, what's really cool about it is that you can take a wire from a Red, White, Black cd audio cable and the end will just slide right into the top of the grabber. It is a little tough to get on there, but it works.

[Nohto]

I have a dif method of doing the mod. For the ground you can solder to the mosfet (see picture) and if you screw up the pad on the left side of the resistor, you can solder to the resistor next to it.(See picture)

[tome]

Originally posted by Radelon
SMD Grabber

That's the one I have, what's really cool about it is that you can take a wire from a Red, White, Black cd audio cable and the end will just slide right into the top of the grabber. It is a little tough to get on there, but it works.

Thanks for this info. I will try that when I get my next IC7.

tome

[Astroman]

I did this mod yesterday, went to Rad Shack and picked up everything, including a 15w Soldering Iron, some "solder wick" (solder braid), some silver solder, a 1kohm 15 turn ceremet (15 turns is PLENTY 1/2 turn works out to be about .01 volt), and some wire.

Everything I needed including the iron was about $22.

I lost my old Weller soldering iron

anyhow, I did the mod with the computer still assembled, I just unplugged everything from the back, pulled off teh side, and set it down on the kitchen table. No more than 10 minutes later, including time to unpack/unwrap all the items, I was finished.

Let me say this is truly a piece of cake if you do it right, using the right tools. The solder wick makes removing the "resistor" a snap, without risk of damaging the PCB. Pre-tinning all the wires, the legs of the VR, and putting a tiny drop of solder on each pad makes the process very easy.

After all is said and done, I have 3.15 vdimm when set to 2.8, but I'm going to start backing that off.

For some reason, even after installing a TrueControl (Antec) 550w I still can't get prime95 stable after 275 FSB.

I can post higher than 300mhz but not get into windows. I can get into windows at 290, but prime fails instantly.

I think this VTT mod interests me now, considering the relative ease of such modifications, I may try it maybe it will help!

Thanks for all the info guys.


Abit IS7
Pentium 4 2.4c @ 3.4 Ghz
vdimm 3.15
Kingston HyperX pc3500 2-2-2-5
277 fsb @ 5:4
Street Racer
Auto
Auto
Auto
Disabled
6.1+ Ghz/sec sandra score
16300+ 3dmark01SE
9500 pro @ ~370/295
Antec TrueControl 550
Zalman CNPS7000 AlCu
1.7vcore

[MnM]

Heres a pic of it:

Originally posted by MnM
Thanks to you guys I have finished this mod.
I replaced the 0Ohm resistor with a 331Ohm one (IC7-G).
It works perfect. At 2.55 selected in bios it will actually give me 2.75. Didnt try any higher yet.

Funny thing is this.
I have done one motherboard first and it worked perfect.
Then I did my friend's one. He would get a blank screen and no post. We replaced the resistor (the 331Ohm one) with a new one, thinking we might have given it too much heat. Same result. No display at all. What I have done then, is I shorted the 331Ohm resistor with some twizers therefore giving it a 0Ohm value.
I got post. I removed the twizers not post.
In the end what I have done is I put another resistor (331Ohm) ON TOP of the 331Ohm already on the motherboard. I solder it in parallel. We turn the PC on - POST!!!!
Now with this mod, he gets only half the voltage from the normal mod eg. 2.55 selected in bios actually gives him 2.67 real volts.
He was happy with it as he already thought he had to spen $$ for a new motherboard. Plus in the end he still gets more than the 2.8 limit.

So 2 identical boards, two identical mods but only one of them worked. I think the components used on the boards and their tolerances play a big part in modding the vdimm. I am now sure that if I had a 400-450Ohm resistor around and would have actually solder it to my friends board will have worked giving him a bit better than just 0.1 increase over the value selected in bios.

Maybe this info can help the guys who cant get a post after the board has been modded. Try solding one to the motherboard and one on top of the resistor. At least you will get more than the defualt max voltage in the end.

[shimmishim]

okay... i've read a lot of this thread and i think i am going to do this mod after seeing how my geil gold dragon keeps failing memtest but is good up to 3.1 volts....

so let me get this straight...
alll i need:
soldering iron (15-35W)
1K ohm (adjustable)
solder wick
solder

i can go to radio shack and get all these things if i'm correct... can anyone give me the part numbers from the webpage so i can know what to get?

so this is the procedure...

i remove the board from my case... lay everything out on the table

find the r50 resistor which is next to the winbond chip right under the vdimm slots.

i am going to place soldering wick or whatever next to the resistor (i have no idea what soldering wick or braid looks like)

then i am going to use the soldering iron to heat up the metal contact pads (two of them) to remove the resistor but i have to be careful not to heat it too much or the pads will be burnt up or damaged

i remove the resistor

i adjust the 1k ohm pot to 300 ohms (i have a multimeter to measure this but i need help as to how to set it because i burnt up my 8rda+ thinking my pot was set to i forget how many ohms)

i take two pieces of wire and connect it to the pot...

then i take the pieces of wire and connect each to the contact pads via some of the solder

and voila! i'm done...

i guess the little details are things such as...

how do i adjust the pot correctly?
how do i connect the wires to the pot (i could just use solder correct)?
what sort of wires should i use?


i think if someone could give me the part numbers from radioshack, that'd be most helpful.. thanks!

Edit: i found all the part numbers on radioshack.com

i guess i have a question about the solder wick/braid

do i place this on the tip of the iron?

[Astroman]

using solder braid is quite simple.

I used my bare fingers with about a 2" strip of braid, though you may want to use a glove or pliers to hold it, it gets hot.

place the end of the braid over the solder joint, then use the tip of the hot soldering iron to press the wick down onto the solder.

This heats the braid, which in turn heats the solder, which melts and gets soaked into the hot braid.

do this on both sides. the "resistor" will probably still be stuck to the board but apply the iron again to one side and it should melt the thin remaining layer of solder and you can gently push the "resistor" off its pads.

good luck.

Don't forget to tin the wire before trying to solder it to the board and the legs of the resistor..

[shimmishim]

what is tinning the wire?

[Ruantic]

Originally posted by shimmishim
what is tinning the wire?

Tinning the wire refers to the process of pre-applying a thin coating of solder to the wire BEFORE you attach it to the connections.

[shimmishim]

okay cool! i'll give that a shot...

i'll try this mod out tomorrow most likely...

keep your fingers crossed that i won't kill this nice board!!!

[shimmishim]

i was practicing on a dead motherboard...

is this a good job of desoldering a resistor?

did i burn the contact pads?

any suggestions?

btw... FB15 is the one i removed

[Astroman]

looks good man, nice job.

If you got the stuff at Rad Shack and followed the directions on the back of the solder braid, then you are doing well!

now, practice tinning the wires and soldering them to those pads.

One thing very important, is that you have to keep the joint STILL once you remove the heat, or you may end up with what is known as a "cold joint" or a bad solder connection... so, remove the iron and keep the wire as still as possible.

I would also like to add that there looks to be quite a bit of splatter on the board... is that how it came ? clean that crap off if you have anything that looks like that on your new board.