ATI 4850/4870 voltmod thread

[NapalmV5]

i tried 22k 10k and got nothing

its 50 ohm




to all involved thank you for the vmods

rock stable @ 900/950 vcore mod/stock cooling


edit: soldered 2 x 4.7k fixed @ mvvdc/mvvdq
now memory stable/comfortably @ 950

[jason4207]

yep, 50 Ohm.

[dejanh]

i tried 22k 10k and got nothing

its 50 ohm




to all involved thank you for the vmods

rock stable @ 900/950 vcore mod/stock cooling


edit: soldered 2 x 4.7k fixed @ mvvdc/mvvdq
now memory stable/comfortably @ 950

Report back after you run FurMark for more than 15 minutes (minimum 1280x1024 res, renamed executable so it is not crippled by the driver). Also, ATITool artifact free for at least 30 minutes

[Mungri]

My bios modding results at stock volts, no screens just yet:

750 / 2000 - 100% Stable
800 / 2000 - Blue screen on boot
775 / 2000 - Boot safe, but causes lockups

I'll stick to 750 / 2000 for now then

[jason4207]

My bios modding results at stock volts, no screens just yet:

750 / 2000 - 100% Stable
800 / 2000 - Blue screen on boot
775 / 2000 - Boot safe, but causes lockups

I'll stick to 750 / 2000 for now then

750 is incredibly good for stock-voltage. How did you test for stability?

[Mungri]

750 is incredibly good for stock-voltage. How did you test for stability?

It ran furmark for a while, but Atimadk thingy crashed in the second test of Vantage

What are the stock volts on the 4870? I just want to modify it to 4870 stock voltage and then try 750-800 again.

[TI66ER]

My 4850 is modded with rbe for 1.158v high 3d and has the overdrive signature from the asus 4850TOP injected into it.I have 800/1300 limits now on overdrive,and it runs fine at 760/1200 using just overdrive to oc it,i am on cat 8.8.

My 3dmark06 score is 14711.

[Mungri]

Thanks so much man, I was about to use 1.3v o.O ....

I'm not silly enough to do that without checking first though. I thought the default 1.047v were a little low and thought 'that cant be right, it should be 1.2-1.3v shouldnt it?'.

lol.

I will try 1.15 and see if I can get 750 Mhz stable in all stress tests now.

[jason4207]

My 4850 is modded with rbe for 1.158v high 3d and has the overdrive signature from the asus 4850TOP injected into it.I have 800/1300 limits now on overdrive,and it runs fine at 760/1200 using just overdrive to oc it,i am on cat 8.8.

My 3dmark06 score is 14711.

And it's 24/7 stable at 760/1200 or just benchmark stable? That's VERY good for that voltage and you must have some good RAM on there too!

Cat 8.8, huh...can you get 8.8 to work w/ low 2D voltage or are you not concerned w/ that?

I think the 4870 has ~1.3v going to it by default. 1.3v on my 4850 got me close to 800, and 1.315v has me stable at 800. Previously I was at 1.35v and 820, but the extra 20MHz just didn't seem worth it.

[Mungri]

I wondered why this wouldn't work for me @ 750 Mhz:




Which voltages do I change? Just 03 and 09? Or others as well?

My 1 Gb cards wont ever go above 1000 Mhz ram, they only reach that with extra ramsinks on the back modules!

I currently have a row of Aluminium heatsinks on top of the thin copper ones, and I'm going to add another row of copper ones on top lol.

They get too damn hot! It would be nice if I could have just found some larger ones.

[jason4207]

I wondered why this wouldn't work for me @ 750 Mhz:




Which voltages do I change? Just 03 and 09? Or others as well?

My 1 Gb cards wont ever go above 1000 Mhz ram, they only reach that with extra ramsinks on the back modules!

I currently have a row of Aluminium heatsinks on top of the thin copper ones, and I'm going to add another row of copper ones on top lol.

They get too damn hot! It would be nice if I could have just found some larger ones.

This is how I have mine set:




This only works for 8.7, though, and my low 2D voltage may be too low for you unless you pencil or hard-mod.

[Mungri]

Yea, I will leave my 2D clocks as they are at 500 Mhz.

Why overclock the 2D speed in Clock info 06?

[jason4207]

I thought 03, 06, & 09 were all 3D. When you click on any of the cells those are the ones that show up as 'mode 3 high' and are in red.

[ante_ante]

Planing to vmod my sapphire 4870 512MB card. Can someone show me a good pic and what ohm pot should i use ?

[jabski]

whats the max voltage that can be set in bios on a 512mb 4870 ??
Thanks

[Tommy L]

i have a sapphire 4870 512mb with blue pcb (109-B50731-11) and i had to scratc away the painting on soldier spot. vmod ok and measure to 1.37v but it would not go higher that with stock volt.. get black scrren with furmark- renamed. passes with stock volt. ok to 840\1190 dont like higher vgpu or what?

[dejanh]

4870 does not like voltages higher than 1.35V - 1.37V on the core. After 1.37V the stability is completly gone. The max voltage will be between those values combined with say 1.6V for the memory.

[JamesBong420]

Planing to vmod my sapphire 4870 512MB card. Can someone show me a good pic and what ohm pot should i use ?

this should be added to the 1st page of this thread.

picture taken from Wizard's guide @ techpowerup..
4870 vGPU

[Barr3l Rid3r]

New Bios mod for use in ATi 4850 512mb Qimonda w/ or without default cooler.

Improovements:

1) Less Clock and voltage while in Idle mode, bringing better durability an lower idle temps.

2) Higher voltage and default 3D VGPU Clock while in FULL load mode (680/1000Mhz).

3) Higher overclock limit in default ATi CCC driver (800Mhz GPU highest setting) and also better overclock ability cause of the higher default 3D voltage.

4) Adjusted Default cooler fan speed adequately, to keep it cool and quiet.

http://rapidshare.com/files/148699499/4850mod.rom.html



And that is custom made one for hardmodded cards.





Idle GPU @ 400Mhz 1.02V







Full Load GPU @ 830Mhz 1.33V




How to


Windows XP, use last Ati Winflash utility, for Vista must do via DOS floppy disk or Pendrive w/ booting abilities.

Pendrive:

1) Get HPBOOT

http://rapidshare.com/files/107282064/HPUSBFW.zip

2) Get BOOT Files

http://rapidshare.com/files/107282214/USB-Boot.zip

3) Unzip All for both and run HPBOOt, select your pendrive, check quick format and create DOS startup disk, files located at: choose extracted folder containing Boot files.

4) Get and unzip ATiflash 3.60 and then copy the extracted files to your pendrive don`t forget the bios file 4850mod.rom linked above.
http://www.techpowerup.com/downloads...lash_3.60.html


5) Set pendrive as first boot and also first disk in your motherboard bios.

Run:

Atiflash -f -p 0 4850mod.rom

[mauronow25]

New Bios mod for use in ATi 4850 512mb Qimonda w/ or without default cooler.

Improovements:

1) Less Clock and voltage while in Idle mode, bringing better durability an lower idle temps.

2) Higher voltage and default 3D VGPU Clock while in FULL load mode (680/1000Mhz).

3) Higher overclock limit in default ATi CCC driver (800Mhz GPU highest setting) and also better overclock ability cause of the higher default 3D voltage.

4) Adjusted Default cooler fan speed adequately, to keep it cool and quiet.

http://rapidshare.com/files/148699499/4850mod.rom.html



And that is custom made one for hardmodded cards.





Idle GPU @ 400Mhz 1.02V







Full Load GPU @ 830Mhz 1.33V




How to


Windows XP, use last Ati Winflash utility, for Vista must do via DOS floppy disk or Pendrive w/ booting abilities.

Pendrive:

1) Get HPBOOT

http://rapidshare.com/files/107282064/HPUSBFW.zip

2) Get BOOT Files

http://rapidshare.com/files/107282214/USB-Boot.zip

3) Unzip All for both and run HPBOOt, select your pendrive, check quick format and create DOS startup disk, files located at: choose extracted folder containing Boot files.

4) Get and unzip ATiflash 3.60 and then copy the extracted files to your pendrive don`t forget the bios file 4850mod.rom linked above.
http://www.techpowerup.com/downloads...lash_3.60.html


5) Set pendrive as first boot and also first disk in your motherboard bios.

Run:

Atiflash -f -p 0 4850mod.rom

hello, I've tested your bios at the CCC the limit is 800 and 1300,
LA if I did try the 720 and 1150 crashes the VGA.
measure with a voltmeter and I have no more than 1.2 volt at full load.
This change does not exceed more than 1.2 volts?
this tension is impossible to exceed 720 mhz and GPU

I hope your comments ..
thank you very much ...
MAURO from Argneitna

[Barr3l Rid3r]

hello, I've tested your bios at the CCC the limit is 800 and 1300,
LA if I did try the 720 and 1150 crashes the VGA.
measure with a voltmeter and I have no more than 1.2 volt at full load.
This change does not exceed more than 1.2 volts?
this tension is impossible to exceed 720 mhz and GPU

I hope your comments ..
thank you very much ...
MAURO from Argneitna

No, the is no way to go further using soft mods, only if u made a hard vgpu or pencil mod.

How is your clocks now? 400mhz/750Mhz idle and 680/993Mhz Full? Did u noticed any temperature improovement?

[Death909]

Anyone aware of a vmod for gainward golden sample 4850s?

[KoHaN69]

I'm having trouble with:



I've used mechanical and wood #2 pencils, and the lowest I could get it is ~1500Ohms

is there any other way to pencil mod?

Is the first mod on resistor illustrated above required for:


?

How do i check the resistance decrease using the second one?

[jason4207]

I'm having trouble with:



I've used mechanical and wood #2 pencils, and the lowest I could get it is ~1500Ohms

is there any other way to pencil mod?

Is the first mod on resistor illustrated above required for:


?


How do i check the resistance decrease using the second one?

I did the pencil before my hard mods. I never did have much luck w/ the 1st pencil point, but the 2nd 1 worked fine. Just measure the resistance b/n the 2 points you're penciling across.

I don't have my notes in front of me, but some typical Ohm values for the 2nd point are buried in this thread somewhere.

[Brumi]

Hy all!

Somebody kwnow any mod with this card: http://www.sapphiretech.com/us/produ...gpid=249&grp=3 ?

My previous HD4850 with pencil mod: Vantage @ 800/2300

Sorry for my bad english...