First Time Voltmod (4850)

[ExodusC]

Hi everyone. This will be my first time doing a voltmod (no soldering, just the pencil mod). I have an HD 4850 cooled by an Arctic Cooling Twin Turbo, and I'm going to try to push it to 750+ on the core, but I need some more voltage.

I've never done a voltmod of any kind, hell, I've never even used a multimeter, so I want to make sure I do everything right so I don't screw up.

First of all, I want to make sure I'm reading the voltage correctly. I looked at TechPowerUp's tutorial, and I saw three places to measure vcore. Here's a picture of my 4850 and where I've been measuring:

http://img207.imageshack.us/img207/2854/vmodah0.jpg

Am I reading this properly?

I have some other questions to come, but I want to make sure I'm doing this properly first.

[adrift02]

Um, I don't know why you have the negative on the other solder point. You ground the negative to a case screw generally (any grounded object) and then measure with the positive end. However, the measuring point is correct.

~1.16v is about normal for the 3d clocks, I would force the 1.158 profile voltage with ati tray tools first just to be sure....wouldn't want to base ur pencil mod measure off the 2d voltage....

[ExodusC]

Um, I don't know why you have the negative on the other solder point. You ground the negative to a case screw generally (any grounded object) and then measure with the positive end. However, the measuring point is correct.
Ah, like I said, I've never used a multimeter before (well I've checked batteries and stuff before, but nothing important).


~1.16v is about normal for the 3d clocks, I would force the 1.158 profile voltage with ati tray tools first just to be sure....wouldn't want to base ur pencil mod measure off the 2d voltage....
I'll check it again when it's grounded to make sure I'm getting the correct voltage. Oh, and I do have my voltage forced in ATI Tray Tools.

[ExodusC]

Oh wow! I did the pencil mod, and I guess I did it right!

I had 1.172v at stock, and now I'm getting 1.332 volts!

I might try again and see if I can get a little more if I keep at it with the pencil (I know there's another pencil mod for more than 1.4v), but I don't think I need that much voltage.

[adrift02]

GJ! :up:

One thing to be aware of with pencil mods (which I just found out), is the graphite becomes more conductive as it gets hotter. What this ends up doing is raising your voltage as your card heats up. At one point I had my card at 1.38v in windows @1158 profile, after getting into a 3d stress the voltage jumped to ~1.4v (which I expected), however, from there it continued to slowly climb over the next hour to over 1.42v and I stopped at that point. This is a downside to not doing a hardmod and basically means you need to get your card to about ~0.04 under what you want as your max voltage. And of course, measure it a lot over a long period of constant stress....

If I was you I would stick to what you got. I gained <1 fps going from 850 to 900.