Athlon 1400MHz 31ºC on idle without fan! (no undervolt too)

jpsa · Post by **jpsa** » Wed Feb 19, 2003 5:59 pm

go to http://www.cpuidle.de/download.html and download the cpuidle prog. It activates the idle function in amd cpu's (these have idle disabled by default)

Now my cpu run's without fan noise (at least when its idle) even listening mp3 it wont get past 35ºc without fan.

My idle temps: (using fan)
- full load 55ºC
- idle without using cpuidle 43ºC
- idle using cpuidle 22ºC !!!

These chipsets are supported:
VIA KT400
VIA KT333
VIA KT266, KT266A
VIA KX, KX133
AMD 760
AMD 760MP
SiS 745
SiS 735
nForce

Cpuidle working together with SpeedFan kick assss!

try it!

BTW- there is a way to do this with WPCRSET / WPCREDIT but uses diferent settings for every chipset

If you get errors in sounds just go to the bios of your motherboard and increase the PCI latency timer. Usually 32 is the default, at 128 should solve all your problems

jpsa · Post by **jpsa** » Thu Feb 20, 2003 12:36 pm

In my athlon xp1600+ (1400MHz) system the idle temps are a lot higher than with the athlon 1400MHz! (both are using cpuidle) the xp idles at 35ºc with fan, the athlon idles at ~23ºC, plus the xp is using a LOT better heatsink... anyone know why this happens?

simmers · Post by **simmers** » Fri Feb 21, 2003 4:24 am

WOW!

Installed CPU Idle and my idle temp dropped by a massive 13C straight away!! With Q Fan operating on my Asus mobo, this meant that my Zalman fan slowed right down and the the PSU did too. Brilliant! This means that I can remove an exhaust fan to reduce noise even further.

This has to be one of the most cost-effective cooling/silencing mods available. My CPU now idles at 32C (from 50C), and that's without an exhaust fan.

Why wasn't this technology included in Windows, if Linux manages to do it?

Chris Ochre · Post by **Chris Ochre** » Fri Feb 21, 2003 7:23 am

It also works for me (Athlon Tbird 1400, KT133), but activating CPUIdle also introduces a high-pitch whine. When I deactivate it, the whine stops. I wonder what causes this?

Chris Ochre · Post by **Chris Ochre** » Fri Feb 21, 2003 8:31 am

It only whines in C2 mode, but this is also the only mode that appears to have any cooling effect. I think I'll have to remove it.

Old mobo...

jpsa · Post by **jpsa** » Fri Feb 21, 2003 8:01 pm

Where does the whine comes from? fans? psu?

Chris Ochre · Post by **Chris Ochre** » Sat Feb 22, 2003 4:53 am

I couldn't tell. It wasn't my CPU fan, as I disabled it an reenabled it to see. I don't have any case fans, and it didn't seem to be coming from the PSU. It seemed to come from somewhere on the mobo, but it's difficult to say where exactly. Either way, it didn't sound too nice.

Asmordean · Post by **Asmordean** » Sat Feb 22, 2003 9:19 am

It doesn't seem to work on my NForce2. I get 33°C (36°C load) if it runs or not.

Gandalf · Post by **Gandalf** » Sun Feb 23, 2003 7:05 am

I don't notice any differnce at all.
Not to mention that it's a shame it isn't freeware.

iom_dave · Post by **iom_dave** » Sun Feb 23, 2003 1:08 pm

find vcool using google - its great

Chris Ochre · Post by **Chris Ochre** » Sun Feb 23, 2003 3:17 pm

vcool still results in a whining sound.

Mark Larson · Post by **Mark Larson** » Mon Feb 24, 2003 7:13 pm

I prefer my processor working instead of trying to maintain it as close to idle as possible.

Also, this is just an artificial method to drop temps - as soon as load increases even by a small amount, your temps will go back to where they were.

shunx · Post by **shunx** » Tue Feb 25, 2003 2:44 am

Very interesting app, dropping my idle temp by 13C. Distorts audio on my computer when enabled.

hvengel · Post by **hvengel** » Wed Mar 12, 2003 3:14 pm

I have used both CPUIdle and VCool. VCool is free and at least on my machine works as well as CPUIdle.

This type of software functions because the OS invokes the HLT instruction when ever it enters the idle loop by flipping a flag in the BIOS to make that instruction to actualy work.

This reduces power consumption in the idle loop by about 90%. So the only time this does not have some cooling effect is when the CPU usage is at or near 100%. Otherwise the cooling effect is in proportion to the amount of CPU idle time. When an Athlon is idle with this software it is only using about 5 to 7 watts.

blakerwry · Post by **blakerwry** » Wed Mar 12, 2003 3:44 pm

I've just always used wpcredit and wpcrset by H. Oda

worked great on my kt266 and 266a...

I believe they all work on the same principle. Win NT based OS's automatically send a HLT (halt) command when they are idle, this is supposed to put the CPU in a power saving mode(c2).. even if idle for only a single clock cycle.

IIRC, the pentiumMMX's were the 1st CPUs to support the HLT instruction ...

However, by default VIA chipsets are set to ignore the HLT command that puts the CPU into this power saving mode. They simply ignore the command and do not pass it onto the CPU. Some chipsets, like the AMD ones and Intel ones, don't ignore the HLT instruction... so users with these boards automatically see the cooling benefit.

What these programs do is modify the CMOS/BIOS settings so that the chipset will now act as it is supposed to and will pass on the HLT instruction to the CPU.

I'm not sure if the NForce ignores the HLT instruction or not, we will soon find out I guess.

Athlon 1400MHz 31ºC on idle without fan! (no undervolt too)

Athlon 1400MHz 31ºC on idle without fan! (no undervolt too)

using vcool of 1600+ xp 27c with zalman