Underclocking

[Geckovich]

Big long post that speaks lots of truth

Well said.

Now to hijack momentarily in a related manner:

I'm trying to underclock my e8500 but keep stock speeds (for noise/temps rather than power consumption admittedly) but my mobo doesn't support lowering CPU volts - is there software which can do this through windows?

Windows 7 RC x64 to be precise.

 

[Bleek]

Hey Ed,

if those figures are accurate and your system is stable then that is an amazing result. I've been tinkering with ULV computing since March 2008 and have never managed to get a system running semi loaded at 25w

The one thing you have done which I never got round too was underclocking the CPU frequency so that may well shave off some extra watts. I'm running an undervolted Stock E5200 @ 1.08vCore and an undervolted stock E8400 @ 0.960vCore with most voltage options dialed down and using laptop 2.5" hard disks that use about 1-2watts.

I managed to halve my CPU watt usage by dropping from 2.6GHz and halved it again going from stock to 0.8v, I'm also using a single laptop drive, no CD rom, under-volted memory and NB with a very efficient 780 AMD chipset. I need to check full load but I estimate around 40watts at max load.

100% load for 10 minutes and the Athlon was still only 37'c and that was in the weekends heat! I'll get my pyrometer on the core to double check it against the probe to be sure.

 

[4T5]

What is this Madness !!!

 

[Big.Wayne]

my mobo doesn't support lowering CPU volts - is there software which can do this through windows?

Not that I'm aware of?

I think the motherboard needs to have low vCore options in BIOS for software controlled vCore adjustment to be possible? ASUS and Gigabyte both have software controlled low voltage options with their latest boards.

I need to check full load but I estimate around 40watts at max load.

I've heard a lot of good things about the AMD 780G but in most of the reviews I read which included power consumption charts seemed to indicate it used more power than the Intel G45 express platform? Your the first person I heard about who has produced a stellar ULV result using the AMD platform!

Look forward to your final results and its made me more keen to underclock and undervolt a bit more to see if I can match your results . . . although I'm at 0.96vCore now and the BIOS only goes as low as 0.850v so I don't see it shaving that much off!

It's a good move to ditch the optical drive, I thought of that too and replace it with an external USB Optical drive that you plug in when you need it but I didn't get round to it yet as they were quite pricey, thanks for the reminder!

 

[waynio]

Hi all
Glad I came across this thread.
I use my gaming rig nearly 24/7 but only just recently started turning it off at night, it is a pretty power hungry rig and I only seem to do 1 to 4 hours gaming most days so after reading this it is obvious to me that I should build a media rig that runs on very low power for normal every day usage and only put my gaming rig on when I want to game.

One thing I am not entirely sure about thou is say if I got a quality 500w psu with very high efficiancy like say 80% to 90% does that mean if the components are using say 100w then that is the power it will draw from the socket or would it be much more? I would like to know this.

 

[Big.Wayne]

it is obvious to me that I should build a media rig that runs on very low power for normal every day usage and only put my gaming rig on when I want to game.

That would seem like a logical conclusion and in fact is one I reached myself last year!

The idea of having two PC's, one ULV box for 24/7 general usage and a second box for high-def gaming is quite gratuitous, if you can afford it then great but I'm not sure everyone will have the spare cash for this luxury!

I've been trying to merge everything into a single machine but am still waiting for a GPU that uses low wattage yet can still provide playable frame rates in most games at 1920x1200

if I got a quality 500w psu with very high efficiancy

If you had a PSU that was 100% efficient then 100% of the electricity pulled from your wall socket would go directly to power all of your components. Sadly as no PSU is 100% efficient then there is a certain amount of energy wasted in the process!

If you had a computer that needed 180w at full load and you were using a state-of-the-art PSU that was 90% efficient then the whole system would pull 200w from the wall socket, 20w just gets *lost* along the way!

I'm bad at maths so someone needs to check the figures heh!

 

[Bleek]

What is this Madness !!!

Look at my signature, I'm flying the clocking flag too.

 

[Bleek]

I've heard a lot of good things about the AMD 780G but in most of the reviews I read which included power consumption charts seemed to indicate it used more power than the Intel G45 express platform? Your the first person I heard about who has produced a stellar ULV result using the AMD platform!

Also remember I'm using the onboard VGA and I've downgraded that too, running 350MHz instead of 500MHz with reduced volts - again absolutely no performance decrease evident in Windows.

Oh and for software voltage adjustments i.e. to lower further than your BIOS allows take a look a this - http://www.silentpcreview.com/article231-page1.html offers a comprehensive (if not dated) guide to optimizing your computer using CrystalCPUID (freeware).

Using the profile manager (dynamic clockspeed management) in CrystalCPUID, you can also set 3 different clockspeeds and VIDs to allow your computer to scale based on processor load. You can underclock/volt down to minimum at idle, and have it scale up to max power when necessary!

 

[Bleek]

One thing I am not entirely sure about thou is say if I got a quality 500w psu with very high efficiancy like say 80% to 90% does that mean if the components are using say 100w then that is the power it will draw from the socket or would it be much more? I would like to know this.

I'd use the smallest PSU you can get away with (200W in my case) - by their nature they inherently waste less power.

Just stay under the 50% load at peak (of 100% effiency) and you'll keep the PSU nice and cool, wasting even less energy.

 

[waynio]

I've been trying to merge everything into a single machine but am still waiting for a GPU that uses low wattage yet can still provide playable frame rates in most games at 1920x1200

That would be a good evolution of tech if they ever get round to making a high end gpu that uses 50 to 100w just what energy consious people want , but you could always underclock your gpu for normal everyday usage and put it back to normal only for gaming, my gtx285 has pretty good power management settings for normal usage and for gaming.

My gigabyte p45-dq6 motherboard supports quite a few profiles

I have the one I'm using now @ 3.6ghz stock volts for warmer ambient temps like 26c upwards
one that is 4ghz for cooler ambient temps
and one that is 4.2ghz for cooler ambient temps
All heavily tested to be stable and very safe temps
There is another profile slot so I think I'll have a play around with that for a low power usage profile for general use, just a shame it does not support disabling cpu cores like my old evga nvidia 680i that would help a lot in getting power usage down with me using a quad, but really I need to buy a power socket measurer so I can really see what I'm using think I'll order one this week, and post back results of the underclock I attempt.

 

[Bleek]

Onboard VGA down from 500MHz to 280MHz and 0.9volts, no adverse effects so far. That'll save me a few watts, ha!