most Gecube cards use voltage dividers to determine the ram voltages...click my siggy....

btw...i got 48XX pts in 3dmark03 with my Gecube 9550GT 600/290 with ultra tight timing. i drop most of the timing to the lowest settings that rabit allowed....

here's my timing:



This post has been edited by Shah81: May 21 2006, 09:08 PM

my ram is TSOP and with that timing at 290MHz i need to pump 2.75V to the ram to keep the tight timing. with slower timing, 290MHz can be achived at 2.6V.

this mod is done to give more current to your AGP slot for graphic cards that dont have their own dedicated power connectors like the 9600XT does. my GPU is running at 1.6V to get to 600MHz. before the mods, anything above 1.5V will not be stable....the 3.3V reading on my AGP slot will droop alot. now my AGP voltage is 0.01V lower than my PSU 3.3V rails and i can use 1.6V on my GPU.


give me a high res picture of your card both front and back and i'll try to help you with the mods.

oh ok...so you upload your pic already...

the circle 1 & 2 are the possible location for your Vmem. one of them will be your Vddq. so what i need you to do is that a close-up picture of those circles. make sure you use a good camera...i need to see the connections and if possible the markings on those components. (use hig res...3mp and up and oh, use thumbnail.. )





This post has been edited by Shah81: May 21 2006, 10:36 PM

ok before i start anything.....do you have a multimeter?? because if you dont have one i wont help..sorry

so you wanna do the mod or not??.... i thought you're good with soldering. your siggy looks impressive with VDD Mod + Vdimm Mod + Vcore Fluctuation Fix.

btw....the multimeter will be used later. not tonight

This post has been edited by Shah81: May 21 2006, 11:24 PM

no problem for me...this mod is simple. i figured it out already. now only need a multimeter and pot to make it work

the parts you can buy from any electronics shop. nothing fancy....normal pot should work just fine.

oh...btw...have you find the point where to measure your Vgpu. if not i can show you where it is

ok in the box no.2, there will be two soldering point. you can measure the voltage at any of these point. if you're on stock cooling, i suggest you stay below 1.5V.



this is normal....it got nothing to do with gpu voltage but more related to your gpu speed. sometime higher gpu will result in a lower mem speed and vice versa. u just have to find the best combo of gpu vs mem speed.
for 9600, i suggest you max out your mem speed first and then work your gpu.

heatsink for the TSOP..yes and a must when voltmodding.
heatsink for the MOSFET...optional. they dont really get hot on my card even after voltmod.

you can cut up a large heatsink to be used on your rams. report here once you got a multimeter. i'll give instructions on how to voltmod your vmem. hopefully i can come up with a pencil mod.

cheap copper ram sink HERE

This post has been edited by Shah81: May 22 2006, 12:18 AM

got your multimeter....good

here's what you gotta do:
first measure your Vgpu....dont let it fry

next look at the pictures below





in the first picture i marked the shunt regulator(labeled as 1) and 2 resistor. although the shunt regulator looks like it have 6 leg, actuall it only have 3. the second picture is how the circuit actually look like.resistor A & B correspond to resistor 2 & 3 but i dunno if resistor A = resistor 2 or 3 in the first picture...so you have to find out yourself (use continuity test) and tell me the result.
next find the resistance at point F and the resistance of resistor A.

thats it for now....give me the result and i'll tell you how to mod it.

works ok for me

measure the resistance with the card out of your pc. point the multimeter to both ends of the resistor to measure resistance.

i cannot show you where point F is because the picture that you gave me is not clear. try taking a close-up picture with macro mode turn on and at highest quality and make sure your hand is not shaking.

you can find it yourself using continuity test with the multimeter. on the shunt regulator, find the leg that is connected to both of the resistor (2 & 3). that leg is Point F. the point where the resistor is connected to the shunt regulator leg is also point F.

for voltmod, u can try to lightly pencil on top of Resistor A (its either resistor 2 or 3, i dunno you have to tell me) or solder a pot from Point F to ground. but i need the resistance value to determine the value of the pot.

very nice picture this time

ok in the picture below, the arrow is pointing at one of the shunt regulator leg. that is Point F. to find Resistor A, test the 2 resistor that i box out. the one that have one of its point connected to ground is Resistor A. the one that have one of its point connected to the mosfet is Resistor B. both of the resistor will have one point connected to Point F (ie: the shunt regulator).



you just marked where is Resistor A & B and where the points on each resistor that is connected to ground and mosfet and the resistance of Point F in the picture. i need to make sure that it is the correct place to mod

ok Good Luck

bro...do you know how to use a multimeter?? do you understand the schematics that i showed above?? i have a feeling that u dunno how to use a multimeter and you dont understand the schematics. if thats the case, this is going to be hard but i'll try my best to help you.


point one of the multimeter probe to the leg of the shunt regulator that i pointed at in the picture and the other probe to ground point (u can use the -ve leg of the capacitor) make sure to set the multimeter to read resistance. start with the lowest setting and change to a higher settings until you get a readings. the available settings will be 200, 2000, 20K, 200K, 2000K.


use the continuity test on the multimeter, the one that have the diode symbol. point one probe to the leg of the shunt regulator/ground/mosfet and the other probe to any point nearby (ie: resistor). if there's a connection between the the 2 point, the multimeter will beep/emit a sound.


for the last few post, i only ask you to measure the resistance and check for the connections. nothing more nothing less.

don't worry...i'll try my best to help you out.