ATI 4850/4870 voltmod thread

[K404]

5K? sounds about right if memory serves...4.8xK at stock?

[[XC] gomeler]

5180 ohms was the stock resistance on the leg of the IC for the HD3850 vgpu mod. At least that's what it was on 2 of 3 cards, 1 was 5120 ohms.

[jimmyz]

yes I meant 5k will fix later.

[gurusan]

Looks much the same as the 3850, I wonder if the same pencil mod will apply?

[By0T0xN]

Looks much the same as the 3850, I wonder if the same pencil mod will apply?

I've been wondering the same thing. If so that would be great to be able to gain a lil without hard modding.

[TI66ER]

could this be the voltmod spot and pencil mod spot?

the layout is very similar to the 3850,after examining my 3850 voltmod,these two look likely spots.

[jimmyz]

I never was involved in the pencil mod thread, I already soldered the 3850's when it was found. none of it matters until a tool is found that lets it O.C. I may hold off on testing the v-mod until something is out. no need since others would rather see benches than mods right now. besides it is at the 700 mhz max easy enough.

[Extelleron]

I never was involved in the pencil mod thread, I already soldered the 3850's when it was found. none of it matters until a tool is found that lets it O.C. I may hold off on testing the v-mod until something is out. no need since others would rather see benches than mods right now. besides it is at the 700 mhz max easy enough.

Have you tried the AMD GPU tool? Rivatuner doesn't work at all? Can the memory reach the 2400MHz allowed in CCC?

I'm really interested in how these cards clock. I would think the 4870 at least should be capable of 900MHz or so, given the 3870's were capable of that once you got a BIOS that allowed you to go over 860MHz.

[K404]

Could you try modding the Riva .inf file with an educated guess of the relevant code based on older ATI models?

Cant hurt....

[jimmyz]

Could you try modding the Riva .inf file with an educated guess of the relevant code based on older ATI models?

Cant hurt....

tried, it see's the card now but no go on the clock setting. just stays stock.


Finished and tested volt mod. it is working. here is a quick walkthrough. The pad beside 601 is perfect for our purpose and easy to solder to.

[IMG][/IMG]

getting the items ready.

[IMG][/IMG]

and done, tested resistance , it checked out, time to fire it up.

[IMG][/IMG]

It works great and btw I believe the v-dimm mod is the same as 3850. I never applied it but in looking at the pic they are verrry close. just a resistor turned etc. will post pics and measurements soon.

[philbrown23]

noice! looks like almost the exact same layout as 3850, except some of the resistors are labeled different.

[jimmyz]

noice! looks like almost the exact same layout as 3850, except some of the resistors are labeled different.

It basically is. It is closer than the non refference 3850's even. I use a jumper for now. since I don't need it until I can clock it up. works fine at 100k resistance it has 1.21v just .01v more than stock. I tweaked it to 1.32 and it was fine scaled nicely with a 15 turn VR.

[Papu]

can wait to see what kinda clocks this thing will reach!

[TheKarmakazi]

nice work jimmyz on the forefront i see ! maybe ill buy your 4850's too when your done with them

[Brother Esau]

You guys are aware that JimmyZ is a Rebellious Amish Overclocker right?

[TheKarmakazi]

You guys are aware that JimmyZ is a Rebellious Amish Overclocker right?

lol

[jimmyz]

calm down now Brother esau or I will have to contact my brethren in S.C........ bye the time you hear the hoof beats its over.

[Jip]

hi someone have test a pencil mod ??

[Alex-Ro]

Barely waiting for results!

[wiak]

TechPowerUp has high res images on their reviews
http://www.techpowerup.com/reviews/P...HD_4850/3.html (botton)
(If you choose to use these images for voltmods etc, please include a link back to this site or let us post your article.)

[G.Foyle]

DId anyone try to flash the bios on this card with existing tools? For example, does atiflash work?

EDIT: Oh wait, there's a new ATIflash release with RV7700 support

[Jip]

it's @ home for me ^^

i test it

[Jip]

yes I meant 5k will fix later.

What brand of memory have you on your 4850 ??

[ghost_recon88]

Is the vmem mod the same as on the HD3850?

[Jip]

arfff i don't realise the pencil mod for my HD4850 Someone can help me ??

Here some pics of my 4850