AMD/ATi HD4850/4870 Fan Fix!

[hstuehmeyer2000]

you guys know you can change the core and memory speed buy using this file right? you also might be able to change the voltage to

edit: you can only edit the clocks within ccc's limits

[Baron]

Where is this file in Vista?


I canny find it.

[tylerw13]

Where is this file in Vista?


I canny find it.

you have to make the folder appear, it is hidden so under the folder options in the control panel select show hidden files and folders then it will show up

[Caveman787]

Well it'll be cooler regardless because it'll get the air being circulated out

The hot air wont be sent out that tiny pci slot very much in my opinion, I think it'll help but I mean how much air can be forced through there? Specially with a fan thats static air pressure is being dissipated over the layers of the copper heatsink.

[Shadowmage]

That's just nonsense. The card does NOT consume less power if it is cooler...
It will consume maybe 1W more, because the fan spins faster, but it will never start producing less heat by being cooler, it can just get rid of the heat easier, making it cooler...

This is actually incorrect... it's well known that transistors leak more current (static leakage) with increases in temperature.

[xMrBunglex]

65% fanspeed took my GPU down to 40° in a matter of seconds, but it's only affecting my bottom card. can CrossFire users make this work for both of them?

[Caveman787]

I'd assume so just do it with each card individually.

[Adhesive]

Wow, setting the fan at 33% took me from 78 to 58 c, and I stay under 65c at load as opposed to 80.

[xMrBunglex]

I'd assume so just do it with each card individually.

i don't know how to do that. i went through the profile in notepad and didn't see any line specifying one particular video card. it's a great fix, but not if it only works on one card.

[Rattle]

so can this work for 2 card in crossfire?

[Caveman787]

I didn't make it so I don't know. But it seems like a bios or instruction set type of mod which each card has so like I said I don't see why not.

Perhap's pm the guy who figured it out?

[xMrBunglex]

i figured it out. there is a section later in the config that starts with "FanSpeedAlgorithm_1". all you have to do is make the same changes to that section that you did to "FanSpeedAlgorithm_0" and it will apply to both video cards.

sorry for being stupid.

[Unbornchild]

so can this work for 2 card in crossfire?

Of course this works in crossfire too. In that file you'll see things double instead of single:
in crossfire, "CoreClockTarget_0" and "CoreClockTarget_1".
same for the other "targets"...

[GoldenTiger]

Just tried this on my now-working-again 4870, went from 78-81c idle temps to 48-50c idle at 34% fan which isn't too loud for me. Very nice!

[Unbornchild]

Btw this thread seems to suggest this is a new fix... it isn't, it appeared around the first days of HD 3870, some of the first batch had a fan- and bios problem (or rather: "powerplay-issue"), this was the most simple and harmless workaround.

[GoldenTiger]

Btw this thread seems to suggest this is a new fix... it isn't, it appeared around the first days of HD 3870, some of the first batch had a fan- and bios problem (or rather: "powerplay-issue"), this was the most simple and harmless workaround.

Cool, I hadn't heard of it back then .

70c load at 34% fan setting with 790core/4400ram... .

[mascaras]

How to recover ATI Radeon HD 4870 from bad BIOS flash

http://www.techpowerup.com/articles/...ng/vidcard/152




now after all of you guys getting the cards working again , i think is better just use this CCC FAN Fix until AMD/ATi get a new one !



regards

[xMrBunglex]

i heard a rumor of a Sapphire fanfix BIOS like they did with the 3870's, but i haven't seen anything come out yet. i'm dull and old fashioned, so i prefer factory BIOS over modded ones.

[Bo_Fox]

That's just nonsense. The card does NOT consume less power if it is cooler...
It will consume maybe 1W more, because the fan spins faster, but it will never start producing less heat by being cooler, it can just get rid of the heat easier, making it cooler...

As your mentor, I tell you, "Go and do some research."

[eleeter]

If we follow Ohm's law, the power consumption of the card will not change depending on temperature, assuming a consistent load.

Or to rephrase it slightly, the resistance of a graphics card stays nearly the same regardless of heat, which must mean the same power draw.

The way I understand it is, when powered on initially, the card absorbs the energy first. When it reaches it's static output/cooling point, the heat is then transferred to the surroundings. If you increase the fan speed, it means the heat is more quickly transferred to the surroundings on start up, and of course this is maintained, and the cards terminal temperature is lower. But the total heat output does not change, in fact it cannot change because it must obey Ohm's law.

But then again, I have quite a bit of electronic experience, but I am no thermal expert so I could be wrong. But to me, because the electrical energy is being turning nearly 100% into heat, it makes sense.

[xMrBunglex]

i think we're officially off topic now. this is a very useful thread as long as it doesn't get derailed too badly. cooler is better. 'nuff said.

[Bo_Fox]

If we follow Ohm's law, the power consumption of the card will not change depending on temperature, assuming a consistent load.

Or to rephrase it slightly, the resistance of a graphics card stays nearly the same regardless of heat, which must mean the same power draw.

The way I understand it is, when powered on initially, the card absorbs the energy first. When it reaches it's static output/cooling point, the heat is then transferred to the surroundings. If you increase the fan speed, it means the heat is more quickly transferred to the surroundings on start up, and of course this is maintained, and the cards terminal temperature is lower. But the total heat output does not change, in fact it cannot change because it must obey Ohm's law.

But then again, I have quite a bit of electronic experience, but I am no thermal expert so I could be wrong. But to me, because the electrical energy is being turning nearly 100% into heat, it makes sense.

I cant remember where there was such a wonderful article showing the numbers and real-world benchmarks, but here's a direct quote from an Intel guy saying:

Matty @ Intel:

Yes, the power consumption is reduced when the temperature of the processor is lowered.

There are many things that happen in a CPU when the temperature is changed and to elaborate further on the processor specific causes we have to look at the origin of the power consumption. We can divide the total consumed power into two main parts, static power (Ps) and dynamic power (Pd).

The static power consumption is what we usually call the leakage. In an ideal transistor, it should completely shut off the channel between the source-drain, gate-source and gate-drain. Transistors are far from ideal, and the current leaks between these parts and the substrate of the processor, and this is heavily dependent on the temperature.
For example, going from room temperature to 85C (~60C difference) increases the leakage power by a factor of more than 50. Thus, reducing the temperature with the same amount will make a huge impact on Ps.

Dynamic power consumption is emitted during the short amount of time that the transistor switches. Lower temperature reduces the resistance in the processor which results in shorter delay/faster switching of the transistors. Shorter delays and less noisy signals also reduce Pd.

I hope this explanation give you some clarity to the relation between power consumption and temperature. This can even be seen with air cooling: The power consumption is lower just after a load is applied compared to after a while when the temperature has levelled out, even though the load is the same.

Here, a link from googling it:
http://www.analog-europe.com/howto/208700231

[initialised]

Ohm's law is a little simplistic for understanding thermals in solid state devices. But these cards (4850 & 4870) run hot and keeping them cool will help with stability at higher clock speeds, reduce the need for BIOS or volt modding to achieve it and prolong their life.

A combination of the fan profiles mod and upgrading the TIM should allow them to reach the limits imposed by Catalyst.

Sadly I have to give my 4850s back tomorrow. Am seriously considering a pair of 4870s now though.

[Shintai]

I doubt resistance change much in the temperature area we work in. Aka 20C to 70C. At minus 100 or 200...sure. Maybe you can save 2W or so running at 20C instead of 100C...ye...

Its not like a 100C laptop CPU uses 500W power...

[Bo_Fox]

I doubt resistance change much in the temperature area we work in. Aka 20C to 70C. At minus 100 or 200...sure. Maybe you can save 2W or so running at 20C instead of 100C...ye...

Its not like a 100C laptop CPU uses 500W power...

There's no such thing as a 100C CPU. Let's start talking some sense and then we will be able to understand the numbers (i.e., power leakage issues that begin to arise as nanotech fab processes shrink from 90nm to 45nm and beyond). Otherwise, the numbers make no sense to you as you bicker on.