How-to: Pencil mod your HD 3870!

[eidairaman1]

they probably view that resistor as not needed.

 

[dark2099]

Thanks for all your help guys.

 

[eidairaman1]

Ok gotcha. Well they probably had some PCBs left over and decided to change the component layout. Silly companies trying to keep us from drawing on our video cards

I wonder if the 3850 Is Volt Moddable.

 

[thoughtdisorder]

This is how you test resistance:

(Note: The orientation of the red and black contacts does not matter when measuring resistance.)

And here is how to measure the resistance of R1222:

Closeup:

You want each tip to be in contact with the metal part of the resistor on each end. That way, a small current generated by your DMM passes through the resistor from tip to tip, and the DMM measures the resistance.

Here is how to measure the resistance of the second pencil mod:

Closeup:

This one's simple. Touch each tip to each metal dot, and read your DMM.

Here is how you measure voltage:

Hope this helps! I plan on doing a full walkthrough on TechFuzion sometime soon.

Nice work Danish, THANKS!

 

[DanishDevil]

No problem guys.

What do you think, a how-to video or a photo walkthrough would be better? The video won't be as clear, but it will show process a little easier than photos.

 

[thoughtdisorder]

I wonder if the 3850 Is Volt Moddable.

I would think so, I mean it only seems logical. Randoms working a double tomorrow, and he's now sleeping, but I plan on asking him when he gets home tomorrow night.

 

[DanishDevil]

I wonder if the 3850 Is Volt Moddable.

Same thing as this 3870 guys, except the resistances and voltages are different.

 

[thoughtdisorder]

No problem guys.

What do you think, a how-to video or a photo walkthrough would be better? The video won't be as clear, but it will show process a little easier than photos.

Video would be good, but overall I would think pics would help the inexperienced more, just my 2 cents.........

 

[thoughtdisorder]

Same thing as this 3870 guys, except the resistances and voltages are different.

That makes perfect sense.....

 

[dark2099]

Ok, I don't know what I'm doing wrong now, but I shade in the area slightly, test the resistance, and it either hasn't changed, so I shade a little more, and still not change in the resistance.

 

[Dr. Spankenstein]

If you are shading the area indicated by the yellow line in the image provided by DanishDevil, you might need to slightly scratch the surface of the PCB in order for the graphite to adhere.

[/IMG]

There is a coating on the PCB that will hinder the shading from "sticking". When you get ready to power-up the first time, be ready to test for voltages as this can be rather unrefined in it's ability to adjust the amount of resistance drop.

 

[dark2099]

Ah, I switched to using a 4B pencil rather than 4H and it seemed to work better, should I erase the 4B and retry with the 4H?

 

[Dr. Spankenstein]

Up to you. Softer only equals, easier to lay down a good trace of graphite.

But when it comes to this particular Ghetto mod, it make little difference.

 

[dark2099]

I think I might not do this after all, got the resistance down to 2.15 from 2.37, voltage is at 1.48 up from 1.34, and ATI tool doesn't want to OC the card now (course I am on a fresh install of Vista 64)

 

[Dr. Spankenstein]

Why! That's a respectable voltage, just dump ATITool and get RivaTuner. You be able to OC and control the fan. Heck, you could even go to *looks around for ATITool agents*, ATI Tray Tools!

 

[dark2099]

Hehe, yea, just gave RivaTuner a test and worked just fine, only when I started scanning for artifacts at clocks I had before doing the mod, I was getting lots of artifacts where as before the mod I wouldn't. Should I use something else for artifact scanning?

 

[Dr. Spankenstein]

No real reason to.

I WOULD suggest that you kick the fan speed to 100% until you get a grasp of what's going on with your new voltages AND clock speeds.

To me, these smaller GPUs are more sensetive to heat than previous fabrications.

 

[dark2099]

Well on the card I am doing the mod right now I have a ThermalTake DuoOrb w/ the goo it came with, hopefully my MX-2 will get here monday, when I will get another TT DuoOrb for my 2nd card and play with that one.

 

[Dr. Spankenstein]

Cool, keep us posted of your progress!

And congrats on having the nuggets to go ahead and pencil-mod that sucker!

 

[dark2099]

Long story short, I picked up a cheap AMD mobo & cpu combo cause it was about that time, knew AMD's were generally easier to OC (or thought atleast when I got it) slowly upgraded parts, and now have become a chronic benchmarker and want to get an Intel setup to improve the current high scores.

 

[Dr. Spankenstein]

NOW yer talkin'!!

Until AMD comes up with a stunner, you will shit bricks when you work with and Intel CPU.

'Nuff said...

 

[thoughtdisorder]

NOW yer talkin'!!

Until AMD comes up with a stunner, you will shit bricks when you work with and Intel CPU.

'Nuff said...

So fuc*ing eloquent! I Love you man!

 

[Wile E]

NOW yer talkin'!!

Until AMD comes up with a stunner, you will shit bricks when you work with and Intel CPU.

'Nuff said...

Yep. I'm glad I made the switch. Benchmarking has never been so fun, now that I can actually compete in the upper tiers.

 

[DanishDevil]

Same here. 4.68GHz on water is really nothing to sneeze at! My E6300 @ 1.86GHz felt faster than my 5000+BE @ 3.2GHz.

 

[Wile E]

Same here. 4.68GHz on water is really nothing to sneeze at! My E6300 @ 1.86GHz felt faster than my 5000+BE @ 3.2GHz.

Is that 24/7 clocks at those voltages, or just bench settings?