Search:

8,1+GHz - I don't think so :p:

@lex, have they really 40 turns? That's pretty nice.

Nice to see they work :)
But change these VRs to proper ones ;)

This is one-turn potentiometer. I wouldn't use it, because a little adjustment equals too big voltage change. Too unstable and dangerous.

I haven't seen any 47k or 470k multi-turn VR's. They must be ~15-20 turn, like these: http://ceemic.pri.ee/hardware/_trimmers.jpg
Usually they are 1k, 5k, 10k, 20k, 50k, 100k, 200k, 250k, 500k etc. ...

You need to measure more. There can't be any difference between GND and AGND.

For Vmem mod I suggest 50k ohm VR.

What is resistance between GND and FB? 1,4k ohm?

petrakov, if You shade that resistor with pencil, Vmem will drop, not rise :p:

This is right:
http://ceemic.pri.ee/hardware/all/up6101_pencil.jpg

But I still suggest VR, not pencil. Mem chips...

petrakov, You can use any spot that is directly connected to FB pin. Use some bigger for easy soldering. The "A" on pic1 seems the best.

Vgpu measuring points:...

petrakov, use search in this thread. Here are many different cards with that IC.
Pin #19 is FB. Look where it goes to find better soldering point. Remove card from PC and measure resistance between...

D0m|nat0R, how do You know OCP is "kicking" in?

@lex, my Asus HD4850 was also very bad clocker. It's probably due to the custom PCB/PWM...

DavyGT, try these:
http://ceemic.pri.ee/hardware/all/hd4850_measure.jpg

@lex, why it can't be 1,25V? Sounds pretty ok. Sadly I don't remember my different HD4850's def Vgpus.

@lex, there is no difference between molex GND or GND near IC; maybe ~0,005V.

DavyGT, then You can use 100k ohm VR.
It depends to what these resistors are connected. I never use pencil-mods and don't recommend it.
For Vgpu You can use PWM cap legs for example. Similar to:...

@lex, why do You measure Vgpu between cap legs? Ofc You have to use a proper GND.

DavyGT. If resistance between FB pin and that point on that SMD cap is 0ohm, then yes, they are connected and You can use that spot for soldering. Now measure resistance between FB and GND.

No, that's #6. See one post above Your previous post here. There is FB marked with green.


EDIT: should be this trace:
http://ceemic.pri.ee/hardware/all/up6201.jpg
That pic is not that good, so...

DavyGT, nothing is different. FB pin is still pin #13. Trace it and find a good soldering point. Measure default FB->GND resistance and You'll have Vmod.

You need to make PCB layout pics yourself, and both side of the card.

Please make layout pics both side PCB. Also all must be visible. Atm, GPU PWM isn't even on that pic.

Nice price on LHe :D

Always double-check all measurements. For example between directly pin4 and pin18.
If 1,1k ohm is right, then 20k ohm VR works fine.

You have to find some bigger GND point near that IC. You found FB allready, so just measure resistance between FB and GND. Remove card from PC before that ofc!