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Help me finish a refrence 7950 vMod.

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Scout

Member
Joined
Sep 9, 2011
At some point this card was vmodded and then disabled for what I am assuming was bitcoin mining, 90% of everything is still there I just need to find out where the last wire goes.
The Previous owner left some clues where there was solder left which I circled in red. The card runs fine and the read point works well.

This will be my first vmodded card, I figured it was time to get on some 3d benches :D.

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That was the first guide I found when I did some research and seems to be the most widely done but it looks untouched on this card. Attached to the card is a 100 Ohm Variable reistior

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vsen.JPG Looks like it could of been solder to the spot where the arrow is pointing to- take a ohm reading form that spot and see what you get
 
It will be a few hours before I can do it but it should be from that point to ground right ? What should I expect to see ohm wise ?
 
Correct that point to ground seems most cards are reading 1.8 ohms since you said there's a 100 ohm Vr it could be more or that was the only VR he had in hand
 
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Okay got about 9.4 Ohm on one side and 2 Ohm on the other with a Sperry DM210A not the fanciest multimeter but it works !
 
I double checked the measurements but they were correct, pin six I had to break out my magnifying goggles but its about 10 Ohm.
 
Scout sorry for being MIA been busy anyway I was trying to figure out if volt modding VSEN pin was like modding feedback pin but came up empty found a couple of cards that the VSEN needed to to be modded of more volts like the hd 6970m and the hd 5850 and both said to use 500 ohm VR and the VSEN read 14 ohms on one and 12 ohms on the other which is probably a little on the safe side if it was me I would of started with a 200 ohm VR and same with your card but of cause I've been wrong be for but one must guess that the volt mod worked if he didn't remove the volt mod completely when he sold you the card

Don't know if you you already said F it and solder to the capacitor already (which is a first for me but makes sense) but if you didn't take a volt reading on boot up with out the mod then after you do solder the wire to the capacitor to the point that the arrow is pointing to in the first pic I posted then watch the volts after the mod and see if the volts are the same if not I would shut it down and add a different VR for better control of the volts
 
Scout sorry for being MIA been busy anyway I was trying to figure out if volt modding VSEN pin was like modding feedback pin but came up empty found a couple of cards that the VSEN needed to to be modded of more volts like the hd 6970m and the hd 5850 and both said to use 500 ohm VR and the VSEN read 14 ohms on one and 12 ohms on the other which is probably a little on the safe side if it was me I would of started with a 200 ohm VR and same with your card but of cause I've been wrong be for but one must guess that the volt mod worked if he didn't remove the volt mod completely when he sold you the card

Don't know if you you already said F it and solder to the capacitor already (which is a first for me but makes sense) but if you didn't take a volt reading on boot up with out the mod then after you do solder the wire to the capacitor to the point that the arrow is pointing to in the first pic I posted then watch the volts after the mod and see if the volts are the same if not I would shut it down and add a different VR for better control of the volts

I really do appreciate the help and its a spare time thing for me as well but now I get to fix the mess I made and replace the cap..... and glue the trace back on the board. Basically a calamity of errors I will post a picture of my mishap lol its ugly.
 
Scout guessing it didn't work out as plan would still like to see pic's to see damage might be able to still help out



I have actually been honing my skills and picking up the required parts ! I decided I needed a little more practice with the iron so I Vmodded a Nvidia 7950GT and it turned out ok.
That cap I was trying to solder to do you know what value it is I picked a kit of smd caps that are 1pF to 10uF so hopefully I have the right one.
 
sounds good brother seem you got it under control (oops just reread post )if you now some one with a good DIMM they could measure uf reading off the old smd someone that repairs ac's .....

EDIT- is your original smd bad or lost guessing lost if order new
 
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sounds good brother seem you got it under control (oops just reread post )if you now some one with a good DIMM they could measure uf reading off the old smd someone that repairs ac's .....

EDIT- is your original smd bad or lost guessing lost if order new

I will post a pic tonight. Trying to get my self ready to graduate and working takes a large part of my free time lol.
 
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