ATI 4850/4870 voltmod thread

[diablos]

sorry guys,
Can you post a photo for 4870 vgpu mod?
wich trimmer can I use?
under watercooling, Which is the max safety vgpu for benchmark and wich for daily use?


thanks

[albon]

Only way to know your OC is satble is to run FurMark on Stability Test, full screen, no AA, for 5 minutes.
This soft heats my 4850 almost 10°C more than 3Dmark, and I m on water.

[W1zzard]

HD 4850 voltmod article posted: http://www.techpowerup.com/articles/...g/voltmods/151

[diablos]

HD 4850 voltmod article posted: http://www.techpowerup.com/articles/...g/voltmods/151

and for 4870?

[W1zzard]

no card here yet => no pics => no article

[gurusan]

update

950/1200 on 1.48v this card is awesome

[bigslappy]

sub'ed
;p

[jason4207]

Only way to know your OC is satble is to run FurMark on Stability Test, full screen, no AA, for 5 minutes.
This soft heats my 4850 almost 10°C more than 3Dmark, and I m on water.

I killed an 8800GT w/ that program. I don't use it anymore.

Best stability test is to play games like you normally do. I use ATI Tool and benchmarks to get a rough idea, and then use actual game play to fine tune.

And some people are just looking to be stable enough to pass benchmarks. No need to run FUR in that case.

When I run FUR I feel like I'm shortening the life of the card. Just my opinion...

[gurusan]

i find rthdribl with 16x multisampling and fleck/bump on to be a very good stability test

So is the Crysis gpu bench

[deathman20]

i find rthdribl with 16x multisampling and fleck/bump on to be a very good stability test

So is the Crysis gpu bench

Yeah rthdribl was my tester of choice, got a little warmer than most things but not absenly hot. Its my temp tester of choice... and usually I can see it error before it crashes so im not getting a hard system crash.

[DemonEyez]

i find rthdribl with 16x multisampling and fleck/bump on to be a very good stability test

So is the Crysis gpu bench

I find the Crysis GPU test a good one for testing memory. If mem is clocked to high or insufficient voltage, I get nice black squarelike artefacts, grouped together. Highly noticabe. Also AtiTool will artefact like helll when running the 'scan for artefacts'

[STEvil]

I killed an 8800GT w/ that program. I don't use it anymore.

Best stability test is to play games like you normally do. I use ATI Tool and benchmarks to get a rough idea, and then use actual game play to fine tune.

And some people are just looking to be stable enough to pass benchmarks. No need to run FUR in that case.

When I run FUR I feel like I'm shortening the life of the card. Just my opinion...

If it died from that program it wasnt a very good card.

[Theta]

Anyone have any fixed resistor values for vGPU or vDDR @ specific levels (i.e. 1.3v, 1.4v // 2.1v, 2.2v)

[STEvil]

If 25k isn't accurate enough then you want a higher value resistor...not a lower one.

I'm installing the mods as I type this. I'll report back w/ my findings.

What?

No.

Higher value means with each turn you are changing the resistance by a larger amount. Lower value allows smaller adjustments to resistance.

[Clemmaster]

Maybe He was talking about higher stock voltage with lower resitance (at its maximum value)?

@Theta: you can find the resistance with this formula : Rnew = Rold*Vold/Vnew assuming the stock values given in the pencil mod we showed

GPU : 1.15v -> 5.12k (stock, 3D mode)
Mem : 2.04v -> 3.94k (stock)

[biftek.]

i would not even think about attempting this mod without a multimeter

I'd just like to point out the seriousness of this post to anyone else thinking of doing this with out a Multi Meter. This really cant be stressed enough.
I was just attempting to go from 1.31 to around 1.36 load.
I applied a couple strokes of my pencil, booted up, measured...
AND WHAT THE ING HELL PANIC ATTACK!!!

It read 1.89V, I kid you not.
Luckily, I had a quick response to hit the switch on the PSU, and no damage has been done, but not having a multi meter I'm sure the chip would have been fried before I got to windows.



Also for those using it, or thinking of using it, I've found the S1 starts to gets over loaded once you start going over 1.4V
The card just heats up till it shuts it self down, and that's with two 120mm fans going.

[Specialfighter]

i will do the mod tomorrow, my is hd is on water i hope i can go to 1,5V

[cowie]

I'd just like to point out the seriousness of this post to anyone else thinking of doing this with out a Multi Meter. This really cant be stressed enough.
I was just attempting to go from 1.31 to around 1.36 load.
I applied a couple strokes of my pencil, booted up, measured...
AND WHAT THE ING HELL PANIC ATTACK!!!

It read 1.89V, I kid you not.
Luckily, I had a quick response to hit the switch on the PSU, and no damage has been done, but not having a multi meter I'm sure the chip would have been fried before I got to windows.

its always a good idea to measure resistance across anything you pencil
before you pencil.
sometimes it is very difficult

[zaraza]

is it hard to volt mod with pencil? what pencil did you use? and how many times did you make a line? i dont have a multimeter but want to try it with my S1 when i get my card/

[gurusan]

yeah I always measure the resistance before plugging the card back in

[tvdang7]

any one having a screen flickering issue? my flickers all the time on desktop. Didnt happen until i flashed with the msi guru bios.

[Freaky]

any one having a screen flickering issue? my flickers all the time on desktop. Didnt happen until i flashed with the msi guru bios.

Meaning it goes off / on in a flash continuously ? Did you try lowering your clocks ?

Errr... Shouldn't you have posted this in the other OC thread ?

[biftek.]

yeah I always measure the resistance before plugging the card back in

Yeah i should have
i made an exception for some stupid reason that time.

Anyways it's back at stock for now, I decided to leave it be for a while

[tvdang7]

Meaning it goes off / on in a flash continuously ? Did you try lowering your clocks ?

Errr... Shouldn't you have posted this in the other OC thread ?

found what it was my memory needed to be clocked lower which is wierd.
before the flashes CCC would be fine at those speeds but with a flash theres flickering. although its stable owell.

im at 740/1025 using bios flash visiontek here.

[jason4207]

If it died from that program it wasnt a very good card.

Well....let me clarify. The main reason my card died was b/c I had mounted the HR03GT improperly, and it wasn't giving equal pressure across the die. I fired FUR up, and after a few minutes the intense heat coupled w/ the uneven pressure made a corner of the die chip off. This is my theory anyway, and I saw the small chip on the corner of the die.

Ever since I've been somewhat scared of FUR...probably for the wrong reasons, but I do feel that you can be game stable w/o having to use FUR to test stability. I use ATI Tool, individual 3Dmarkxx test loops, and Crysis benchmark.

What?

No.

Higher value means with each turn you are changing the resistance by a larger amount. Lower value allows smaller adjustments to resistance.

I see what you're saying. I worded it wrong. My point is that...

If I start at 100k, and you start at 25k I need to turn my VR 3/4 of the way (19 turns) just to get to the same Ohm value where you're starting.

If you assume 25 turn then relatively speaking the 25k will have 1k/turn while the 100k has 4k/turn, but the 25k starts so low that it doesn't really matter how accurate it is.

I'm unsure what vGPU would pop up on the DMM if you started w/ a 10k maxed out, but I know I wouldn't try it. I think 100k is plenty accurate, and I wouldn't use anything dramatically lower.