XFX 9800GTX+ Vmods - Help Needed -

[3BABY]

Hey Guys,

have noticed there is a few non-reference 9800GTX's around, it seems XFX has used a different PWM controller to what is used on the reference models, i cant seem to find any real or downloadable datasheets or information from other card vmods using this chip, below is a pic of the unit, and another chip i suspect my have the mem side of it, any help would be much appreciated.

We have a RT8841 below





uP6161S14 EGF7AF, the syspected mem voltage controller below





and a pic of the relative positions on the board

[ceemic]

I'm pretty sure FB on RT8841 is pin #4. Measure its default resistance between GND and use 20x times VR to be safe. Vgpu should change a little bit even on max resistance on VR. Or You can make some turns to lower the resistance few %. If Vgpu doesn't change at all, then unsolder the VR...

[3BABY]

Originally Posted by ceemic

I'm pretty sure FB on RT8841 is pin #4. Measure its default resistance between GND and use 20x times VR to be safe. Vgpu should change a little bit even on max resistance on VR. Or You can make some turns to lower the resistance few %. If Vgpu doesn't change at all, then unsolder the VR...

thanks for the reply,

ive managed to get the datasheet, and from what it says FB is pin #6. so it should be the one with the green arrow in the second pic?

[ceemic]

3BABY, can You share this datasheet? FB is pin #6.

[3BABY]

Originally Posted by ceemic

3BABY, can You share this datasheet? FB is pin #6.

ok, i screwed that up a lil, have edited my above post to reflect the new info.

datasheet can be found here (note wont be there forever 10times apparently )

[Riska]

The mod works i have made it on a xfx 9800gtx+ and i used a 50k ohm vr for vmem and a 100k ohm vr for gpu

[Tommie_lj]

im planning to buy a XFX GTS 250, wich from what ive heard is the same card as this one? so is it possible to vmod it exactly as this one or is there another mod for that card?

[largon]

If hardware is the same then the mod works.