Help me pencil my HD38x0

Alright.

Here is how to do it.

The DMM: I trust you measure with ohms and also know how to measure voltage under load by using the DVOM (or "DMM" as we call it) and making contact with a vcore measure point while loading ATI tool. To measure ohm resistance on the actual resistor, what you do is put the resistance to something like 2k on the DMM and set your needles on each side of the resistor.

As far as pencils are concerned: I used a 2B pencil from walmart haha. Many users will say 4B is the way to go, but my 2B drawing pencil worked fine.

The actual penciling: I strongly encourage you to measure the ohm resistance before penciling. Your target is going to be ~900-1000ohms, with the stock ohm resistance in the ~1750ohm range. When penciling, pencil with medium-light pressure, since you are dealing with sensitive components. Have a can of compressed air nearby. After penciling for 5 seconds or so, blow the can of air (or with your mouth, just dont spit) to remove the excess graphite. Measure the ohm resistance. Repeat as necessary until you reach your target.

My results overclocking/vmodding this card:

Stock clocks/no vmod:
Resistance: 1756ohm
Voltage: 1.269v
Clocks: Stock 668/828
Max Temp under ATI Tool: 62c

Overclocked/No Vmod:
Resistance: 1756ohm
Voltage: 1.269
Clocks: 770/999
Max Temp under ATI Tool: 65c

Overclocked/Pencil Vmodded:
Resistance: 913ohms
Voltage: 1.417v
Clocks: 857/999
Max Temp under ATI Tool: 77c

For all the above stress tests, fan was set to 75%. This was the single slot Diamond 256mb HD3850, as linked in my sig. Performance with the vmodded overclock can be viewed by checking out my benchmark thread.

The picture below is of a HD3870 PCB, but the two are the same. The only difference is the Vcore stock, 1.33v on the HD3870 versus 1.27v on the HD3850. It shows your vcore measure point as well as which resistor to pencil. R1222.

Quote:
Like CPUs, some GPUs overclock better than others on the same voltages. So yes, you should achieve higher overclocks after adding additional voltage via the pencil mod.

I use rivatuner to OC all of my graphics cards. You might have to use a modded bios to unlock the higher clocks, I used ATIWinflash to flash in windows.

You pencil the top of the resistor, that should be enough. Measure ohms after each penciling of 5-10 seconds until you get your desired resistance.

You use your DMM to measure voltage. Set the readout to DC volts and move the cables in your DMM if you need to from the ohm plug to the Voltage plug. Not all DMMs need this I don't believe, but most do.

After the vmod, install the card and boot into windows. Open ATITool and start scanning for artifacts to load the card. Go into your case and touch the red needle onto the vgpu measure point shown in the picture. Then place the black needle onto your ground, such as the metal on your case.

Post your results! Always keep your fan running fast when you are temperature testing, you dont wanna burn the card!

Quote:
That is what I mean. Nothing is the same at all. I have looked at a ton of pics. But I think i am close.

Just by looking at where the groups are I believe i have found it. The resistance is 2.5k ohm and the only voltage reading i could find that I would assume is the core is 1.02v at idle.

I am confident enough that this is it so I am going to do a very slight pencil and see if the volts go up.

UPDATE: That was it

1.7k ohm
1.31v under load

53c with fan at 75%

core 769
mem 909

Well I tried to oc some more and at 1.31v and 820 core i had it hard lock in tf2.

So here is my new settings.

R1222= 950 ohms
volts= 1.38v load
core= 830
men= 925
fan= 85%

Also I used OCCT to test my oc and I like it alot better. ATI Tool loaded at 55c and OCCT w/ fullscreen loaded at 70c
I will try tf2 later on.

Also should i leave gpu recover turned on?

Edit: I was wrong on ATI tool. i just ran it for about 15 mins and it got to 65c