4870 voltage

I imagine this has been discussed somewhere... I just can't find where!

Does anyone know if there is any known way to get the 4870's beyond 1.15v? Like a custom/different vbios or softmod maybe? These things don't usually even break 70c at the speeds in my sig. Seems like they'd have some real headroom if we weren't limited to 1.15v

 

I've been looking into this myself. Haven't found much though.

 

Have you tried Radio BIOS Editor (RBE) and then flash the cards with atiflash?
Be sure to save a copy of the original vBIOS (with GPU-z per ex.) Just in case.
Cheers

 

yes, unfortunately, 1.15v is the highest option.

 

Don't let RBE limit you, just type in the value you want, i would go with increasements of 0.5V and test each time.
Just be careful .

Cheers

 

It won't work for whatever reason. If i flash the cards with 1.2v, i get a bluescreen while windows is starting.

 

Stock or overclocked?

 

I think you mean .05v. I haven't tried using RBE to manually go to 1.2v, so I'll try that next. However, does anyone know what the upper limit of the card's voltage is?

 

Yes, 0.05V sorry abot that, I'm doing my best typing on my phone(on a boring day of work)
Also not all cards are the same so one might not reach the others settings,just go until you find instability. That's the fun part about it.
These cards are pretty stable at stock voltage so overvolt only if needed.

 

you guys are runing some preatty extreme voltage

if would have set my card to 1.2 i'm sure i'd be cooking and eg on my laptop's back by now

and beside i can reach 600 core and 950 mem wih 1.06

 

This is what I said, start playing with frequencies first and give them juice only when they're thirsty (as your risk of throttling will raise if combined with some CPU oc.)

 

I have not been able to exceed 1.15V with my 4870s trying both the R1 and R2 vbios's. The BSOD is the voltage somehow causing the driver to crash, same behaviour I have seen. Guess you have to have a limit somewhere for overclocking...ours is whatever 1.15V allows.

 

Nah, considering how low the temps are on these things, 1.2v would be nothing. I rarely see temps in the 70's with my sig clocks and 1.15v and even Furmark can't get them much higher than 75C. The desktop variants run as high as like 1.265v at stock speeds. These are the same chips as the desktop 4850/4870, they are just undervolted/underclocked for laptop use.

Your card seems a little more stable than mine. I have to go to 1.15v if I want rock solid stability with anything over 600. I could probably do something more like 650/1075 with 100% stability. I can get them to run at 666-675ish for a little while, but I'll eventually get a blue screen. I figure with 1.2v or 1.25v I could get them stable at 700-725 and probably not ever break 80C in most games. I would find that perfectly acceptable for regular use as the desktop variants run in the high 80's at stock speeds. Throttling might be an issue, but i'd rather that be what holds me back instead of not even being able to try it.

 

I am stable at 670/1120 24/7 no artifacts or problems 1.15v

 

i'm not runing the same laptop as the rest of you guys so 1.06/600/950 was stable on a cooler but since i'm moving around alot lately and can't brign them along with me i backed to 1.05/550/850

when i get some time on my hand i'll test how far i can get on a cooler