ATI 4850/4870 voltmod thread

[Dirton]

Hi, I’ve been running Diamond XOC BIOS for two week now and it's absolutely one of the kind. It lets me OC using manual fan speeds through CCC and that is really convenient. It's just that diamond didn't modified their fan speeds and card gets even more overheated, before flashing this BIOS I defiantly recommend adjusting fan speed first. I just change lower level from 58 degrees till 49 degrees and the card gets nice cool and quiet 71 degrees on donut test.
By the way vendor’s subsys ID on my card (Club3D) and Diamonds were the same.

Now comes the question.
The guy, named guess2098 in this thread mentioned that it is possible to BIOS vmod 4870 till ~1.3V by using some new method, but unfortunately his to busy to answer. Does anybody know how to that exactly, I need certain vid's to write into RBE, or maybe it's done with HEX editor?
Thanks!

[Alcibiades]

Now comes the question.
The guy, named guess2098 in this thread mentioned that it is possible to BIOS vmod 4870 till ~1.3V by using some new method, but unfortunately his to busy to answer. Does anybody know how to that exactly, I need certain vid's to write into RBE, or maybe it's done with HEX editor?
Thanks!

It's NOT possible my friend, I wish it was
But real tekkies have made this absolutely clear
There is no soft vcore bios mod or trick to give your 4850/4870 more juice to core or ddr's through bios
you have to do a HARD mod fullstop period end of discussion.

He input higher values through RBE and flashed his card
then he ASSUMES that just because he's now stable at higher clocks it must be the increase in vcore that's responsible
But does he even have a DMM to measure the actual REAL volts??
No, no he doesn't, nope nope nope
anyway, I see he got some fast reps so he's happy

p.s anyone know if there's a way to soft mod the 4870's with more volts?

[SNiiPE_DoGG]

It's NOT possible my friend, I wish it was
But real tekkies have made this absolutely clear
There is no soft vcore bios mod or trick to give your 4850/4870 more juice to core or ddr's through bios
you have to do a HARD mod fullstop period end of discussion.

He input higher values through RBE and flashed his card
then he ASSUMES that just because he's now stable at higher clocks it must be the increase in vcore that's responsible
But does he even have a DMM to measure the actual REAL volts??
No, no he doesn't, nope nope nope
anyway, I see he got some fast reps so he's happy

p.s anyone know if there's a way to soft mod the 4870's with more volts?

I don't think that question could be asked any more times.

a mod should sticky to the top of the video card section and this section in bold: NO YOU CANNOT RAISE VOLTAGES ANY OTHER WAY THAN SOLDERING ON A 4870!!!

[NCspecV81]

Anyone happen to know the stock MVDDQ voltage for the HD4870? I'm using a 10k ohm resistor on it, and no matter how low I turn it's always reflecting 2.08v on idle and 2.10v on load. However, MVDDC I can tune extremely accurate with a 10k ohm pot.

[Dirton]

a mod should sticky to the top of the video card section and this section in bold: NO YOU CANNOT RAISE VOLTAGES ANY OTHER WAY THAN SOLDERING ON A 4870!!!

Well it's just not right, digital VRM and no soft voltmod.... only a matter of time someone unlocks the BIOS.
By the way 4850 can be vmoded through BIOS, here's currently known VRM generated voltage steps:
1048
1082
1123
1153
1156
1158
(There is a theory that there is now lower limit, but driver doesn’t let you apply lower then there is in BIOS)

Well can take if there is now way to upper default voltage limit, but I at least need to make 2D voltage lower before applying soldering/el. glue VMOD. Isn't that what Power Play 2.0 should be all about?

[Skauneboy]

Anyone happen to know the stock MVDDQ voltage for the HD4870? I'm using a 10k ohm resistor on it, and no matter how low I turn it's always reflecting 2.08v on idle and 2.10v on load. However, MVDDC I can tune extremely accurate with a 10k ohm pot.

Mine reads 1.51 for both MVDDQ and MVDDC.

[NCspecV81]

Mine reads 1.51 for both MVDDQ and MVDDC.

Why would mine showing 2.0-2.1v w/o a VR on it? I haven't done a pencil mod and I've flashed to the ASUS TOP bios. My MVDDC reads 1.51v at stock levels.

[dejanh]

Stock MVDDC and MVDDQ volts are 1.501V. Your resistor is too high. Get a 25-step 5k trimmer.

Well it's just not right, digital VRM and no soft voltmod.... only a matter of time someone unlocks the BIOS.
By the way 4850 can be vmoded through BIOS, here's currently known VRM generated voltage steps:
1048
1082
1123
1153
1156
1158
(There is a theory that there is now lower limit, but driver doesn’t let you apply lower then there is in BIOS)

Well can take if there is now way to upper default voltage limit, but I at least need to make 2D voltage lower before applying soldering/el. glue VMOD. Isn't that what Power Play 2.0 should be all about?

Just because it is digital does not meant that you can adjust it digitally. Maybe it has some default preprogrammed voltage states you can switch between, but cannot go outside of regardless. These are very likely outside the scope of the card BIOS. Either way to put it simply, there is not and will be no BIOS voltage mod for the 4870. But, I guess you can always keep hoping :p

[NCspecV81]

Stock MVDDC and MVDDQ volts are 1.501V. Your resistor is too high. Get a 25-step 5k trimmer.



Just because it is digital does not meant that you can adjust it digitally. Maybe it has some default preprogrammed voltage states you can switch between, but cannot go outside of regardless. These are very likely outside the scope of the card BIOS. Either way to put it simply, there is not and will be no BIOS voltage mod for the 4870. But, I guess you can always keep hoping :p

There is not a resistor on it any longer as I pulled it to make sure it wasn't an incorrect pot or position in the dial, but It still reads 2.0-2.1v on the MVDDQ. It's the same voltage regardless of the present of the pot or not.

[dejanh]

There is not a resistor on it any longer as I pulled it to make sure it wasn't an incorrect pot or position in the dial, but It still reads 2.0-2.1v on the MVDDQ. It's the same voltage regardless of the present of the pot or not.

Are you talking about a 4850 or a 4870? If it is a 4870, I'd take that thing back fast because it will blow up any second. The critical voltage limit for the Qimonda 40X GDDR5 chips is 2.00V.

[NCspecV81]

Are you talking about a 4850 or a 4870? If it is a 4870, I'd take that thing back fast because it will blow up any second. The critical voltage limit for the Qimonda 40X GDDR5 chips is 2.00V.

Okay, I guess it's going back to bestbuy for an exchange. Think there could be something bridged on it?

[dejanh]

Okay, I guess it's going back to bestbuy for an exchange. Think there could be something bridged on it?

Sure seems like you have a short somewhere. Either way something is very wrong.

[LuxZg]

NCspecV81 - why don't you flash it back to stock to check just once more.. Maybe ASUS did something veeeeryyy naughty in their BIOS (somehow)

[DJSUB]

i'm completely noob with this.
i just want to ask what settings to use in the digital multimeter to measure the voltage?
i already killed 2pcs. 4850 because of the pencil modding without a multimeter

how can i measure the idle & load voltage of the card?
is it safe to measure the voltage while benching or doing some stability test to get the load voltage?

sorry for my bad english

thanks!

[Dirton]

Yes, it's safe as long as you don't touch nearby contacts. In load PCB gets about 100 degrees, so try to do it quick until you burn your fingers.
Set direct current voltage on your multimeter.

[DJSUB]

ok.
while penciling the blue one



does the vmem measure point in the image below is the one to check the resistance? or the one i'm shading in the image above?




sorry.

thanks

[drizzt5]

I'm preparing to pencil mod my 4850, I just got done doing a bios flash. I can't clock any higher then I could before (I think I can clock lower) and an unusal thing happened. On load i used my DMM and it said that there was 1.3v's going through the vgpu....

All i did was flash the bios ? I don't think it's suppoused to go that high?

Did I measure it wrong? If I don't have something properly grounded will it measure higher then it's suppoused to? And I'm still on the stock cooler for the moment (my s1 is sitting right next to me, ready to go) and my temps seem good. I don't think I'm measuirng correctly. But I tried all 3 of the vgpu spots that I know of.


Anyone have any suggestions?

[NCspecV81]

NCspecV81 - why don't you flash it back to stock to check just once more.. Maybe ASUS did something veeeeryyy naughty in their BIOS (somehow)

I did, and it was fubar. Not sure what happened there. I exchanged it and flashed to the ASUS TOP bios again. Everything is fine. Volts are matching on both memory voltages. I just got it soldered up a minute ago and I'm testing'er out!

[LuxZg]

NCspec - at least you got your new card right away

Btw, RBE 1.13 is OUT! and it has some niiiceee features like overdrive limits unlocking and lower 2D voltages for 4870 cards Check it out here!

[dejanh]

NCspec - at least you got your new card right away

Btw, RBE 1.13 is OUT! and it has some niiiceee features like overdrive limits unlocking and lower 2D voltages for 4870 cards Check it out here!

Wow, this really makes the 4870 XOC BE obsolete now, lol

[LuxZg]

Wow, this really makes the 4870 XOC BE obsolete now, lol

Well, let's just say it this way - it gives you a choice Now you can add lower 2D voltage to ASUS bios, and add even higher Overdrive settings.. Btw, just popped into my head few minutes ago. This "tweak" allows lower 2D voltage. But maybe it alows voltage CHANGES in general
So maybe it's now possible to bump voltages a bit in BIOS just like 4850's allowed - that would be nice

[largon]

Almost 800 posts and there's people killing cards left and right AND some even have edge to recommend others to falsely RMA'ing the cards they killed due to their own sheer cluelessness. I wonder how many "noobers" have butchered their cards already... Dare I even start backtracking the thread?
Sorry to be blunt, but that's just f'ed up.

[gurusan]

killing cards left and right?

Only 1 or maybe 2 people because they were morons and penciled without a multimeter.

[dejanh]

Yeah, I really only noticed a couple of people killed their cards too. Maybe I missed some. However, I do agree that modding without a DMM is a very bad idea. Worse yet, soldering if you do not know how to do it.

[jimmyz]

Almost 800 posts and there's people killing cards left and right AND some even have edge to recommend others to falsely RMA'ing the cards they killed due to their own sheer cluelessness. I wonder how many "noobers" have butchered their cards already... Dare I even start backtracking the thread?
Sorry to be blunt, but that's just f'ed up.

Anyone who RMA's a card they screwed while modding needs a long vacation

It is clearly stated in the forum rules and these things need to be enforced, Grow a pair and admit you pooched your card not Best-Buy.

The rules since no-one reads them:

10. Theft, Fraudulent activities & RMA's
The management of this Forum does not condone theft, trading in stolen property, fraudulent return of merchandise, or the aiding and abetting of those who do. Any such discussions regarding stolen property or fraudulent returns will be dealt with swiftly, and the offending member risks complete loss of membership privileges in our Forums.