XFX 7900GX2 Vmod, need help!

[funkflix]

Hi,

i have the 7900GX2 and really want to try a mod for Vgpu, but i don't know if the layout is compareable to any other nVidia card? So i tooked some pictures of the card, maybe some guys here can help me to find out the mod?!

There is this part on the right side on the back of the card:


And on the left is this IC:


Full view of the card:


Hope someone can help me and thx a lot in advance!

Regards

Edit: The layout looks a bit like the one from the 7900GTX, and it is the same IC (ISL 6534CRZ).

[fhpchris]

Full view of the card:




That card is MASSIVE! WOW!

[funkflix]

Yeah, it's really big!

The IC that is a bit cut off in first pic:

[vudoodoodoo]

LOL WTH it's even longer than the 7950GX2. :O

[funkflix]

One of the cracks here want to help me please?

[funkflix]

Pleaaaase xs pimp my gx2!

If i should mesure anything, just tell it to me, it is no problem! I will do almost everything to get this baby modded!

[xpsentity]

Vr-Zone has a guide on modding the GX2. Look there.

[funkflix]

Thx, but it is for the 7950.

[funkflix]

One more try.. Anyone?

[SF3D]

First measure values from those resistor marked in picture. Then calculate size of variable resistors you are going to use. Measure voltages also, so you can see which voltage raise when you lower resistance

Intersil 6535crz: VGPU: That is REFIN method. Decrease resistance--> higher voltage.

Intersil 6549: VMEM. Decrease resistance--> higher voltage.

[funkflix]

Wow!

Did u already used this Mod, or i'm teh first one to do it?

Thx a lot!

[SF3D]

You might be first one , I don't have this card.

Good luck and report back if there is problems.

[funkflix]

Ok, will give it a try soon, hopefully i do not damage the card..

Thx mate!

[funkflix]

Ok, here are the values of the resitors.



Which vr i should use for Vgpu?

[SF3D]

Use 20Kohm vr. (Just to be sure)

This is easy tool to calculate vr values or something else.
http://hyperphysics.phy-astr.gsu.edu.../dcex3.html#c1

[funkflix]

Thx. But just have 5K, 10K and 50K at home!

10K will be safe too? If not, i will use teh 50K and adjust it to 20K.

[SF3D]

With 10Kohm, voltage sholudn't go much higher than default, but still try 50K first.

[funkflix]

Thx!

Do u have any idea for a Vgpu messuring point? I tried this one*, but it do not worked.

*


Edit: Hmm, my multimeter was broken.. *g*

[funkflix]

Ok, the Vgpu mod u painted in is not really one! Vgpu stays on 1,27V but the picture on the screen is totally broken, a lot of artefacts.. Thank god that my card is working again, after i removed the VR!

[SF3D]

OK.
ISL 6534 must be Vmem then. (same vmem controller in 7900GTO)

Could you check this value?

[funkflix]

Just the value from this red point to ground? I messured teh resistor in front of it before, and it was 3,8 mOhm. Will messure it.

[SF3D]

Next thing. Which end is ground?

[funkflix]

[SF3D]

There shouldn't be any problem with these mods

Hmmm...there is two parts in this card. (Two separate pcb) Is that other pcb identical?

[funkflix]

Hmmm...there is two parts in this card. (Two separate pcb) Is that other pcb identical?

Yes, this part is identical.

But something is wrong. Hmm, stupid question but which pin on the vr is ground? Sorry, i'm out of the electronic part since years..