Leadtek Nforce2 board: need to volt mod

[LardArse]

Hi guys. I need to volt mod my Leadtek Nforce 2 board. There are so many chips on board I'm so confused.
There's

HIP6301CB <------ Near CPU and AGP
H0210CAXS

TS6121A
0225

HIP66
018CB
P214KCF

W83L78 <---------- Near Memory
5TS-S
234GB

GD7532 <---------- 2 of these
25K
EDYO

W83783S
21110550
205GB

IR
IRU 3007
CW 0133

IR
3037A
CS206

APM9410 <---- 2 of these
OE182

APM7313
OE8A9

74LVCQ6AD
KOL61603
Pnn0207A

There're all scattered about. Was hoping that Guru DDTung could help me out as I only get 2V max and 2.7V max! Got a range of VR ready! Just tell me the pin to solder to ;)

[DDTUNG]

HIP6301 for Vcore. Pin 7 to ground.

Need some pics of the board around the dimm slots to help me figure out the Vmem mod.

DDTUNG

[LardArse]

Thx DDTung!
I dont have a digicam... Can I just list down the chips lying around the Dimm slots?

[DDTUNG]

Originally posted by LardArse
Thx DDTung!
I dont have a digicam... Can I just list down the chips lying around the Dimm slots?

Yes, particularly those located near MOSFETS.

DDTUNG:cool:

[LardArse]

Ok, now there are 3 identical chips situated among the 6 mosfets so i would be guessing they are related to the mosfets. Their code is

HIP66
018CB
P214KCF

Next, this one is very near to the Dimms

W83L78
5TS-S
234GB

and this is made by the same company as the chip found near the AGP which is
W83783S
21110550
205GB

And there are the following 3 chips near the Dimms.

APM9410
OE182

APM7313
OE8A9

IR
3037A <----------Somehow my hunch is on this one
CS206

Thats it. Thx for your generous help DDTung

:)

[LardArse]

I have an idea. Since my DDR voltage is controlled by jumpers, do you think if I set to 2.5v and measure the resistance on every pin and then set it to 2.7v and repeat, the pin's whose resistance changes is the pin?

[LardArse]

Any updates? Any ideas where to search?

[LardArse]

I know The memory voltage regulator is usually located near some mosfets in the dimm area.
Here's the board layout
http://bravo.ausgamers.com/lardarse/lard/leadtek-board1.JPG
The APM chips refer to

APM9410
OE182

and

APM7313
OE8A9

Its either one of the APM chips right?

[Ace-a-Rue]

Originally posted by LardArse
I have an idea. Since my DDR voltage is controlled by jumpers, do you think if I set to 2.5v and measure the resistance on every pin and then set it to 2.7v and repeat, the pin's whose resistance changes is the pin?

WARNING....TRY AT YOUR OWN RISK. DOING THIS MOD VOIDS ALL WARRANTIES!

This should be relatively easy since the Iwill KK266 board used jumpers to raise the VIO.

1st thing you need to do is find the Mosfet to measure your Vdimm. Even if the bios gives you a reading I found on my board that the bios was reading low by minus .08 volts.

Be careful with the probe when you are measuring the Mosfet legs to find the correct one. Slippage can occur:) and possible quick short can happen. Most likely the result will be the video goes out. If that happens, power down or reset should take care of it. The best way to measure the mosfet legs is to use a single wire attached to a SMD grabber. Also, I would set the Vdimm to 2.5V while doing this procedure. Once you find the leg and know what is your actual Vdimm, we can now proceed.

You will solder your 22 or 24 gauge multi-strand wire to a spare jumper. You use the exposed brass/copper crossmember to solder the wire to it. Use a very low heat soldering iron around 15W. The other end of this wire will be soldered to the middle lug of a Radio Shack 10K pot. Depending on what direction you want to turn the pot to decrease resistance (this will increase Vdimm) will determine which outer lug you will use to solder the ground wire. It is best to check the 10K Pot resistance first and then set it to the maximum resistance. WARNING, REMEMBER WHICH DIRECTION INCREASES RESISTANCE (reduces voltage), IN FACT, DIAGRAM IT ON PAPER SO YOU DON'T FORGET!

After soldering your ground wire to either outer lug (maximum resistance set), you then attach the other end of the ground wire to an electrical grommet that allows you to insert a fastener to ground to the case or motherboard.

Make sure power is removed by unplugging the power cord from the PS. Remove the original Vdimm jumper and replace it with the one you soldered the wire to. Make sure ground is hooked up. I would set it a 2.5V 1st. The whole idea behind the jumpers, you are changing resistance by changing jumper positions for the various Vdimm settings. So, you will be in control of the resistance now through the 10K pot.

Usually 10K set with 2.5V Vdimm system will give you about 2.75V Vdimm straight out from boot up. Now measure the Vdimm to see if there is an change in the actual voltage. If the voltage didn't increase then very, very slowly start decreasing the pot resistance. Allow for the system to catch up with the change. So wait about 15-20 seconds between interval changes to see if the voltage has increased any. If no change in voltage is occuring, then power down and switch the jumper to 2.6 and reset the resistance to MAXIMUM. Start all over again until you start seeing some movement in the voltage.

There you have it....give us feedback.:)

[LardArse]

Woo, much thanks to you! Didn't think of this way of adjust mem voltage.
There are 2 jumpers to set my memory voltage. Do I just use either one of them?
I'll be trying this real soon! Thanks! :D

[Ace-a-Rue]

Start with 2.5V Vdimm default 1st. If it doesn't work there, then go to the next jumper position.

[LardArse]

What I mean is, the jumper to be replaced with the resisted jumper. There are two jumpers to move around. Which of the jumper should be replaced or do I just pick one and work from there?

[Ace-a-Rue]

Yes, pick one and work from there.

[LardArse]

Hi. It doesn't work. I've tried replacing both jumpers and tried 2.5, 2.6 and 2.7v jumper settings and tweaked the pot even all the way but there is no difference.
But I found out the mosfet that i measure my memory voltage from. Its here.
http://bravo.ausgamers.com/lardarse/lard/vmem.JPG
So that APM chip nearest to it has the biggest chance? Any ideas?

[Ace-a-Rue]

Ok, the one that is just south of the Mosfet between the 2 donut type regulators could be the Vdimm controller IC.

So, power down to remove the modification and set the Vdimm for 2.5. Now, use a DVM to measure each leg resistance. My DVM is a small no multiple scale so the max resistance scale on mine is 10 Mil. To find the correct pin, I always got 0.6 or 0.7 reading from the leg. All the other legs were way out so it will be obvious when you read it.

Another thought; does your Vdimm jumper(s) have to be set in pairs to get your Vdimm voltage? If so, then maybe you will have to do both jumpers with either a single or two 10K pots attached to both jumpers.

[Ace-a-Rue]

And if that IC doesn't give the readings that you would be looking for, then try the other APM.

[LardArse]

0.6 as in 0.6k ohms? It seems not one leg is there. Would it be most probable that the leg would have below 1k ohm?

[Ace-a-Rue]

Originally posted by LardArse
0.6 as in 0.6k ohms? It seems not one leg is there. Would it be most probable that the leg would have below 1k ohm?

I think 0.6M ohms because my meter is on scale up to 10M ohms.

It could be this one that you said was near the dimms:

W83L78
5TS-S
234GB


I would search Winbond to see if you can find the data sheet.

[LardArse]

Thanks DDtung and Ace for your help. I've already passed the board to my friend. There's another problem with this board's core voltage in which it will not bootup at voltages over 2v unless I boot up first and then tweak my pot for it to go over 2v. A restart will cause bring back the problem so I've had enough of this board.

[Ace-a-Rue]

The 2V is an overvoltage problem. Some boards are more sensitive than others.

Which IC do you use to regulate the Vcore?

[LardArse]

I used the HIP6301 chip.

[Ace-a-Rue]

What you can do is put a 100K RS pot on leg/pin10 and send it to ground. That should give you more headroom for the overvoltage. You might even try a 200K one to make sure you get more.

Like this (green SMD grabber):

http://www.thenakedreview.com/index.php?p=showarticle&id=80&showpage=2