8800GTS 512Mb (G92) vMods

[mAlkAv!An]

Can you get another close up / high res pic of that area? And of the naked front too?

FB pin is pin 22 but its not possible to follow the trace on the pic.

Do you need the vMEM mod too? If so please check the writing on the other IC(14 legs) below.

[aussie-revhead]

The lower chip looks like "APW7067N MK8M3" , I will try to get a better pic as requested.

[Masterchief79]

Jep, that's the vMem IC. Here's the datasheet: http://pdf1.alldatasheet.com/datashe.../APW7067N.html. The first chip, with 14 legs, is the one you need, as you can see the 6th pin is the FB pin (it's always counted from the marked nook of the chip).

For the vGPU Mod: You should be able to measure the resistance of the 22nd pin of that ST Chip directly at the pin itself. After that, I would measure the resistors around the 22nd pin, and check if any of them has the same resistance as the pin.

[mAlkAv!An]

No, Pin 4 is the feedback pin of the PWM controller. Pin 6 is used as FB for the built in linear regulator

[Masterchief79]

Apparently, i'm an idiot. FB and FBL... Of course malkavian is right

[aussie-revhead]

Can someone show me with pictures?

:-)

[mAlkAv!An]

Sure

You always have to count pins counterclockwise starting by the small dot on the IC.

[aussie-revhead]

Sorry for the basic questions but the above pic is vmem mod? VR across those pins? What value? Is the pic in post 651 then vcore mod? VR to ground? What value?

Thanks.

[mAlkAv!An]

Yes this is vMEM mod.
You put a VR between the feedback/vsen and any ground. To tell you the VR size you have to measure resistance between feedback and ground first.
Post #651 is Vcore mod but as I already said it's no possible to spot alternative mod points on this picture, the IC pin is really tiny.

[aussie-revhead]

OK I will try again for a better pic shortly.

[aussie-revhead]

OK I have some pics but I better email them to preserve the detail levels (and too large for posting here)

:-)

[mAlkAv!An]

Ok, got your PM and you got one back :-)

[aussie-revhead]

Thanks, email sent but big pic alert lol

[mAlkAv!An]

Ok, please have a look at your card. Can you confirm that's the conducting path' way?

[aussie-revhead]

I did a probe around the area and it seems that you are very close, I have marked the pic in yellow where I get continuity, yes including the pin next to it (#21?) .

From what I can see the resistance from vgpu FB to ground is about 781 ohms , and vmem FB is 643 ohms, so what size VR's will I need? vmem pins are decent size but the vgpu points are all so tiny ....

[aussie-revhead]

I also need read points for vgpu and vmem.

[mAlkAv!An]

I did a probe around the area and it seems that you are very close, I have marked the pic in yellow where I get continuity, yes including the pin next to it (#21?) .

From what I can see the resistance from vgpu FB to ground is about 781 ohms , and vmem FB is 643 ohms, so what size VR's will I need? vmem pins are decent size but the vgpu points are all so tiny ....

Looking at your pic the trace seems to be different than what I've labelled. Usually you can follow the pathway by eye. In most cases it will cross some resistors which can be used as alternative soldering points. To verify this just measure resistance at those spots - it has to be the same as on feedback pin.

I also need read points for vgpu and vmem.

I've labelled some readings points on the pic. It's always a pair which means that one leg is ground(negative pole) whilst you can measure voltage on the other one:




Regarding the VRs I would use a 50k for vMEM and 20k VR for vGPU mod.

[aussie-revhead]

I did a probe around the area and it seems that you are very close, I have marked the pic in yellow where I get continuity, yes including the pin next to it (#21?) .

From what I can see the resistance from vgpu FB to ground is about 781 ohms , and vmem FB is 643 ohms, so what size VR's will I need? vmem pins are decent size but the vgpu points are all so tiny ....

What I mean is - probing from #22 to all components in the area you indicated I found continuity to the 5 points I marked in yellow- 4 resistor points and pin 21. The second resistor your marked (that I didnt confirm in yellow) does not seem to make a circuit there. It is difficult to get my probe onto pin22 but I rechecked a few times to confirm my findings.

Last questions- what should default voltages be and how far should I increase them? What is safe voltage and max benchable for these?

If I can dig up the components I will have a go tonight.

[aussie-revhead]

OK guys, its messy but its running, default voltages appear to be :

vgpu idle 1.10v load 1.22-1.23v
vmem idle 2.08v load 2.07v

I fitted my VGA supreme to it too, its idling now at 21c so temp wont be an issue, testing now ....

:-)

[aussie-revhead]

OK vgpu mod didnt work, it looks like earth point isnt good, whats the best earth point to attach to?

:-)

[aussie-revhead]

OK I got it running and while xs was down I went by memory, turned the wrong pot and popped the card.... its dead ... Im looking for another now to try again ....

[mAlkAv!An]

Sorry to hear that. Actually any ground point should work well if the wire is soldered correctly. I usually use ground pins from PCI-E power plug, screw holes or mounting points from VGA outs.

[aussie-revhead]

PM coming....

[aussie-revhead]

OK guys, this 9800GTX+ is going well now its got the water block on it, 1.4v doesn’t help much but 1.5v takes it to 920 core, 20,215 3D06 and 325k AM3 , but after this point the voltage adjustment loses sensitivity and jumps up too fast causing loss of graphics, is this OCP kicking in? Any time I change the voltage too quickly the display blacks out and I need to reboot to get it back, thats fair enough as the voltage change is upsetting the vid card but I rebooted at 1.55v then started 3D06 and the display blacked out again, what do you guys suggest? Is this OCP? I wanted to try a little more juice but it doesnt seem to want me to. I used a 20K 10-turn pot, should it have been a 10k instead? Also clocking the 2600K up (from 4.7Ghz base clock) doesn’t help at all, it is still just gpu limited? Which benchmarks like XP better? Will 3D06 gain any score with XP or only the older benchies? Is vmem/vddq worth the gain or is it too risky?

[aussie-revhead]

Ok guys, I ripped the vmod dot out of my 9800GTX+ .... so now Im looking for another card to try again.... is a vmod available for this XFX GTS250?

http://imageshack.us/photo/my-images/41/img02991.jpg/

Cheers.