ATI 3850/3870 Voltmod thread

[Vatos_locos]

1.43 and 100*C it's fanny :p send your card for rma now mine has 1.7V and 45*C on water i guess 60-70 on air ? but noway 100

[-DC-]

re-instelled zalman for the 3rd time, now have 85 degrees... hm... VERY strange)

[Vatos_locos]

try without the mod, what temps you have ?

[Random Murderer]

re-instelled zalman for the 3rd time, now have 85 degrees... hm... VERY strange)

what thermal paste are you using?

[-DC-]

now it's Zalman, tried Alsil-3 also, it was always great)

[Random Murderer]

now it's Zalman, tried Alsil-3 also, it was always great)

that may be your problem. i used mx2 when i installed my vf900 and with the core at 1.44v and 920MHz, i rarely see higher than 65°C.

[spajdr]

Any pencil mod for 3870X2 yet?

[-DC-]

paste cannot be reason of 15-20 degrees) and i also use alsil-3 for cpu. This paste has already been used by me for 4-5 years, and it always had worked great

[Random Murderer]

Any pencil mod for 3870X2 yet?

not that i know of. if you wanna donate one to me or lend me one i could figure one out though

[Clint]

-DC- 100*C is far away from good man my vga @ 1026 has 45*C under watter i think it's time to rma sorry

Clint just go for the 3870 IMHO 3850 with 512 is not a value for money

Well, I pay half the price for the Gigabyte 3850 512MB so its certainly better value.

[Hola77]

I'm thinking about buying the Gigabyte HD 3850 512MB version.
I know this is the image from the prototype, but maybe the memory is still the same on reatil?
What brand is it, from pic it looks like Qimonda?
I believe with those components the core will be very responsive to a voltmod.

That picture doesn't represent the real card in retail. My card has hynix memory that runs at 700MHz I overclocked the memory though and it runs 900Mhz now.
Of course the quality components give high hopes for good clocks when doing a voltmod, but because of the different PCB the layout of the card is different from the rest. So I can't figure out which resistor to shade. If you could figure it out that would be great. I would try it right away.

[Vatos_locos]

Clint if it is like that then ok go for it :p

Hola77 post a good pic of your card

[GenTarkin]

guys I need help =(
I hope I didnt ruin my card...Sapphire 3850 256MB

I have had the pencil (method 1 on R1222) resistor for about 2-3 weeks now..
The core voltage since this mod has been 1.38v
Speeds @ 830/2025

I recently got:
http://www.newegg.com/Product/Produc...82E16835226018

It keeps my core much cooler, except for I noticed in DDO it is within 8C degrees(all other games so far are only 60-80C) of stock cooling @ 80% constant which is 85-93C.
This cooler does not have little heatsinks to cover the 8 mosfets and 4 big square things on back of card...which the stock cooler did cool a little.

with the new heatsink I was playing DDO all day fine on saturday...then at night it started locking up( the video ) about 5-15mins into the game...
Today its still doing it, I tried lowering my core speed down to 800mhz and still does it =(

Do you guys think its simply just a lack of cooling to handle 1.38v?
Do you think that I need cooling on those 8 mosfet and 4 square things (power circuitry section) like the old cooler?
I plan on getting AC S1 to cool this card better.

Or, do you think in combination with the 90C+ temps in DDO all day saturday...and my 1.38v mod...that I have permanently damaged the core? =(

[jimmyz]

I ran my 3850's naked as jaybirds except for danger den maze 4 blocks and used 1.55v and never had issues. been on them since day one,( about a week after launch.)

[Vatos_locos]

when i was running the card with no cooling at the back mosfets and Vcore 1,75 a sound like "boom" came up ! on mosfet dead so i prefer to cool her now so i did that on the photo plus a 4cm fan blowing on the ram coolers and replaced the dead parts

[GenTarkin]

so you think my card is ok and its just lack of cooling?
but no permanent damage?

[Vatos_locos]

yes something like that if you are planing not to give more voltage active coolin is not necessary

[GenTarkin]

well...tonight I tried a dedicated EPOWER juice box to the card, still the same problem...but as I was taking the juice box back off and putting in my normal PCIE plug...ROFL...there was this big dead fried bug on the PCB of the card, I was like WTF?!??!?! that wasnt there a few days ago when this started happening and I took out the card...
So, it was either the bug...
Or a few days back I also lowered the chipset voltage by a notch on my board, I went back in bios, raised its voltage back up...

and now the card works for 1hr + in DDO so far...
so Im happy the card is back and running...what caused it not sure ROFL.
big nasty bug on PCB Bug or Chipset voltage.

[Barr3l Rid3r]

I'm thinking about buying the Gigabyte HD 3850 512MB version.
I know this is the image from the prototype, but maybe the memory is still the same on reatil?
What brand is it, from pic it looks like Qimonda?
I believe with those components the core will be very responsive to a voltmod.

3870 comes w/ DDR3 Qimonda 1.0ns
3850 comes w/ DDR3 Hynix 1.4ns

I need VGPU and unlocked bios for that card, any unlocked 3850 w/ qimonda chips should work.

[Random Murderer]

3870 comes w/ DDR3 Qimonda 1.0ns
3850 comes w/ DDR3 Hynix 1.4ns

I need VGPU and unlocked bios for that card, any unlocked 3850 w/ qimonda chips should work.

i thought the 3870 came with .8ns samsung gddr4?

[Clint]

3870 comes w/ DDR3 Qimonda 1.0ns
3850 comes w/ DDR3 Hynix 1.4ns

I need VGPU and unlocked bios for that card, any unlocked 3850 w/ qimonda chips should work.

I found a mod, but in a lingo that I can't understand

It seems like the tutorial is based on the exact same Gigabyte card though.

Maybe someone here can translate? http://www.extrahardware.cz/voltmod-...d-3850-na-3870

[ORVILLE]

My Gecube PCB is slightly different to most others. It does not have the resistors that are used for most other pencil mods. As well as that, bios voltage mods do not work for this board (deafult always stays 1.25v in both 2d/3d).

Anyhow here is the pencil mod that works for me. BE WARNED - do not reduce the resistance too much - one or two strokes of a 2B pencil is enough and always use a volt meter. My first attempt ended in 1.76v being fed to the GPU.

Default Resitance OF 2.44K gave me 1.25v and 770Mhz limit
Modded Resitance at 2.2K gives 1.42v and 877Mhz Crysis stable

[Barr3l Rid3r]

I found a mod, but in a lingo that I can't understand

It seems like the tutorial is based on the exact same Gigabyte card though.

Maybe someone here can translate? http://www.extrahardware.cz/voltmod-...d-3850-na-3870

that's just bios modifications that do nothing at all, I need an unlocked bios for Gigabyte 3870 w/ DDR3 and VGPU eighter, can u take a clear picture of the back of the card and post here?

[MonsterMash]

Hi, there is a pencil mod also for the vmem?

[Random Murderer]

Hi, there is a pencil mod also for the vmem?

there was one, but i know that for me it only caused artifacts.... whether it actually works or not, i dunno, but i didn't leave mine on.