ATI 3850/3870 Voltmod thread

[NapalmV5]

BUMP!

is that the original bios?

heres what i use..
http://www.iax-tech.com/video/3800biosmod/03.htm

set the 3D structure state "overdrive" @ 800/1000

your 3850 may/may not need the 1.254v

flash bios thru atiflash

but have you oced the card to 800/1000 yet ?

make sure the oc is stable before you flash

[OdinEidolon]

is that the original bios?

heres what i use..
http://www.iax-tech.com/video/3800biosmod/03.htm

set the 3D structure state "overdrive" @ 800/1000

your 3850 may/may not need the 1.254v

flash bios thru atiflash

but have you oced the card to 800/1000 yet ?

make sure the oc is stable before you flash

yep, the oc is absolutely stable, ive not flashed yet. the screenshot shows the bios i wanna put in. is there any limit to the lowest clock i can give it in 2d mode? oh, and a big THANKS!

[FragZero]

I bought a cheap HD3850 256MB a month ago, and i did some mods on it

Vgpu Mod
Accelero S1 + slow 120mm fan, really silent
3870 Ram heatsink
Sawed of VRM part of the stock heatsink


With 1.45V i can reach 920 mhz stable ( 15min furmark 1280x1024 8xaa ), but the temperature gets to 70°, with atitool my the max temp is about 55°, anyone else with a Accelero S1 and 38*0 that can test at my settings ?

I'd like to go a bit higher on the core speed, but i have no idea what the max safe vgpu is ( 1.5v ? )
I'v read here about replacing a few condesators for a higher overclock, but i have no idea what cond. should be replaced, and the amout of µF , any help with this ?

And my last question, would i benifit from a ram vmod ? I'm running my ram at 1000mhz now, max 1050mhz, going from 800->1000 didn't matter at all, is there really no ram bottleneck on these card with a core <1000 ?

[ownage]

I bought a cheap HD3850 256MB a month ago, and i did some mods on it

Vgpu Mod
Accelero S1 + slow 120mm fan, really silent
3870 Ram heatsink
Sawed of VRM part of the stock heatsink


With 1.45V i can reach 920 mhz stable ( 15min furmark 1280x1024 8xaa ), but the temperature gets to 70°, with atitool my the max temp is about 55°, anyone else with a Accelero S1 and 38*0 that can test at my settings ?

I'd like to go a bit higher on the core speed, but i have no idea what the max safe vgpu is ( 1.5v ? )
I'v read here about replacing a few condesators for a higher overclock, but i have no idea what cond. should be replaced, and the amout of µF , any help with this ?

And my last question, would i benifit from a ram vmod ? I'm running my ram at 1000mhz now, max 1050mhz, going from 800->1000 didn't matter at all, is there really no ram bottleneck on these card with a core <1000 ?

I'm using a Sapphire hd3850 256mb for a month now. 1.53vgpu and 950mhz full stable. I probably can lower the volts, but didn't test it.
Max was 1053mhz benchable @ 1.83vgpu (OVP sucks)
I don't know if 1.53vgpu is safe or not, time will tell

My ram is 1000mhz stable without heatsinks or active cooling, just naked ram.
ram vmod would help but a bit to much and the card will die.

[Ket]

I'm thinking about putting my 3870s "under the iron". Their both sapphire cards. I'll start with the more curious of the 2 3870s. One is a hybrid, sporting a 3870 binned core and using GDDR3, without any mods at all this card pushes 900+core 2GHz mem. I might sound a tad selfish here but I'm rather upset with those speeds The memory on the card is rated for 2GHz and is Quimonda, but is clocked @ 1800, so I feel the memory should be able to push at least an extra 100MHz. Before I get into hard-modding I suspect the BIOS on this card may have something to do with crappy memory clocks, its version is 010.080.000.001.000000, I've never seen a HD3k series card with a BIOS anywhere near this late. Heres a LINK to the 3870 DDR3 for anyone that may need it. So the long and short of things, does anyone have this card and has anyone managed to use a different manufacturers BIOS on it? I've tried a few but drivers won't work right once installed.

[NapalmV5]

yep, the oc is absolutely stable, ive not flashed yet. the screenshot shows the bios i wanna put in. is there any limit to the lowest clock i can give it in 2d mode? oh, and a big THANKS!

i wouldnt go below the default 2d.. its already low


well.. heres my 3rd 3870 512MB @ 1ghz+ stock cooler/air

diamond 3870 @ stock cooler/air cooling/default voltages

1020/1380 passed/no vmods

the best 3870 out of the three

edit: 1st mod: bios flash 2nd mod: as5

1150 core after vgpu ?

[OdinEidolon]

i wouldnt go below the default 2d.. its already low

yes, i know, but my card is club3d, they are stupid, default 2d are 700/900 . whats your 2d clocks?

[FragZero]

I'm using a Sapphire hd3850 256mb for a month now. 1.53vgpu and 950mhz full stable. I probably can lower the volts, but didn't test it.
Max was 1053mhz benchable @ 1.83vgpu (OVP sucks)
I don't know if 1.53vgpu is safe or not, time will tell

My ram is 1000mhz stable without heatsinks or active cooling, just naked ram.
ram vmod would help but a bit to much and the card will die.

What heatsink are you using ? And could you run Furmark 1280x1024 8x AA for me ? ( with temp monitoring ofc).

[NapalmV5]

yes, i know, but my card is club3d, they are stupid, default 2d are 700/900 . whats your 2d clocks?

thats probably the uvd colcks

^ 300mhz.. if thats too low set it @ 500.. at least thats what 4870 is @

200.. 100.. should work.. below 100 itll get funny

[Ket]

I set my gpu @ 625 for 2d and video playback, it is deffinately higher than needed, but the muscle is useful for me all the same. FYI I wouldnt set 2D and VCD clocks too different, it can cause endless VPU recovers if for example your trying to watch a dvd and do some photo editing at the same time on another display. guess the catalyst drivers arent very good at switching between clocks.

[OdinEidolon]

thats probably the uvd colcks

^ 300mhz.. if thats too low set it @ 500.. at least thats what 4870 is @

200.. 100.. should work.. below 100 itll get funny

here it is the stupid stock bios...

[NapalmV5]

here it is the stupid stock bios...[/IMG]

lol

heres the 770/975 bios from http://www.iax-tech.com/video/3800biosmod/03.htm




set your stock bios to:

[OdinEidolon]

lol

heres the 770/975 bios from http://www.iax-tech.com/video/3800biosmod/03.htm

thanks, i'll try that out. dunno why but my (latest version) RBE isnt able to read it, i'll try to download it (the bios) again

[SkY-ScRaPeR]

Hi ...
Thank God ... Finally I've found helpful people like you guys


I have DDR3 powercolor 3870 & as u can see in the Picture .. I cant find the resistor R1222 despite it is written on the board ..
I have the GPU O/Ced to 823 Mhz only & need to increase it another 50 Mhz @least ...

Please I want someone Find for me the Specific RESISTOR & which resistor to shade cause I couldnt find it myself ...

Here is the photo link of my PCB :-
http://www.abload.de/image.php?img=dsc0393007n.jpg

Thanx in advance .

[ceemic]

SkY-ScRaPeR, can't see the picture. Please use another upload site.

[SkY-ScRaPeR]

SkY-ScRaPeR, can't see the picture. Please use another upload site.

This upload site is working, I tried it many times & it worked ..

I appreciate any help about this topic from you people ...

Hey here is another link for my card Pic :-
http://i37.tinypic.com/20f42g6.jpg

[ceemic]

SkY-ScRaPeR, OK, now I can see it also. Is the marking on the IC "NX2422"? If so, then pin 13 is FB and the trace should be this: http://ceemic.pri.ee/hardware/nx2422.jpg

[SkY-ScRaPeR]

SkY-ScRaPeR, OK, now I can see it also. Is the marking on the IC "NX2422"? If so, then pin 13 is FB and the trace should be this: http://ceemic.pri.ee/hardware/nx2422.jpg

Hi ceemic ,
I might not understand many electronic aspect as I am only a Dentist

The green marking is resistor & I measure it finding a " 0.00 " result,
That means it doesnt have a resistance,,

I may measure every resistance & post it's result for you to help me decide which one is the target to shade .

[ceemic]

SkY-ScRaPeR, is the resistors, which You marked, other side GND?
You have to find a place, where You can "connect" FB with GND.

[SkY-ScRaPeR]

SkY-ScRaPeR, is the resistors, which You marked, other side GND?
You have to find a place, where You can "connect" FB with GND.

sorry I didn't mark it,, this photo is not from my own capture .. I brought this photo from another person's site ..
But here is my own Capture taken yesterday with my N95 :-

[ceemic]

Measure, if the blue point marked is GND. If so, You can shade between the two spots marked with green:

[roadie]

I'm thinking about putting my 3870s "under the iron". Their both sapphire cards. I'll start with the more curious of the 2 3870s. One is a hybrid, sporting a 3870 binned core and using GDDR3, without any mods at all this card pushes 900+core 2GHz mem. I might sound a tad selfish here but I'm rather upset with those speeds The memory on the card is rated for 2GHz and is Quimonda, but is clocked @ 1800, so I feel the memory should be able to push at least an extra 100MHz. Before I get into hard-modding I suspect the BIOS on this card may have something to do with crappy memory clocks, its version is 010.080.000.001.000000, I've never seen a HD3k series card with a BIOS anywhere near this late. Heres a LINK to the 3870 DDR3 for anyone that may need it. So the long and short of things, does anyone have this card and has anyone managed to use a different manufacturers BIOS on it? I've tried a few but drivers won't work right once installed.

I have a Gigabyte 3870 GDDR3. I can push the RAM up to 1050Mhz no problem, but my core clock is limited to below 860Mhz. Might you be able to provide a link to your Sapphire BIOS so I can check it out on my card?

[patrickadizzle]

i wouldnt go below the default 2d.. its already low


well.. heres my 3rd 3870 512MB @ 1ghz+ stock cooler/air

diamond 3870 @ stock cooler/air cooling/default voltages

1020/1380 passed/no vmods

the best 3870 out of the three

edit: 1st mod: bios flash 2nd mod: as5

1150 core after vgpu ? :D

Hi I have a question. How is this even possible? Is your card a very special batch or something?

I cannot go over 860 core, I can't even imagine how you got to 1000+.

Also how did you allow your overdrive to go beyond 885? I'm not trying to disprove your results, I'm just extremely curious! :D

Let me know m8.

[Ket]

3 words. Radeon BIOS Editor GPU speed though.. either he is using a BIOS that allows him to set a good 1.35v or more, or hes vmodded the core.

[Renegade_!]

Hello all,
Yes, i'm new here, but hey, I've been registered over at OCN for a while now.
I asked there to try and find a pencil mod for my 3850, to no avail, someone recommended I try here, so here I am.

The card is a Gainward HD3850 512MB GDDR3. I can not use the "unlocked" bios as seen above due to the memory allocation on that bios being only 256mb, and I get some horrid vga warping going. Worse than a NES that's crashed.

I figured that my card is also locked in the bios, as I can not break 740/922 without artifacting, or crashing my games...

If anyone could help, that would be extremely awesome, because i'm dissapointed after I managed to OC my HD3650 to 975/1100 without crashing... and 740/922 is just weaksauce. Also, does anyone else find that OC's read wrong on GPU-z?

Thanks for your time.