Underclocking

Soldato
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A break from the norm, I've been working on a low energy ultra quiet work PC, for home.

I've got an ASrock A780GM-LE (780G Socket AM2+) mATX, a Dual Core Athlon 5000+ Black Edition, 2GB Geil Dragon DDR2, 1 x 40GB Maxtor 200W PSU and no other devices.

I've managed to clock the Athlon down to 2GHz at 0.78v down from 1.4v and the memory down from 1.8 to 1.65v! It uses 5w at idle and runs at 31'c stock AMD cooler even in these hot conditions (ambient of 29-31). It'll only get cooler as the weather calms down. :D

The whole system is consuming less than 25W in general use (tested at the wall socket), that's what you call cheap computing and it's by no means slow (I trade so use large charts and spreadsheets).

Anyone else had fun underclocking at all? :)
 
Bigwayne is the man to speak too - He was thinking of starting a sub 100w@load club.

I try to overclock with the mobo minimum vCore - had my [email protected]@1.25v on my IP35pro and [email protected] on my P5Q. And I save a good few watts by not using fans :D

Found that it was only 20w more running my E6600 at 3.4 that 2.4 without a voltage boost - Felt that was a reasonable trade off. Always had my mobo at min vcore since :D
 
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I must say that is a huge drop on voltage...

i've got my AMD 5200+ running 1 volt at 1.4 GHZ (tho i've never stressed test)
might have to run the stress test while lowering the volts... how low can u go??? :p
 
Well I have to say I've had great experience with ASrock in the past and this board is no exception, the voltage changes are in 0.01 increments and can down as low a 0.5volts for the cpu?! Madness. :)

I might see what I can boot at those volts.

I'm really pleased with 2GHz @0.78v though, that's ultra efficient surely?

Any bets on 1.8GHz at 0.65volts? :p
 
Which athlon is that i have the brisbane 2.7 only trouble is my mobo only goes down to 1.3v core :(
 
What minimum cpu speed could you get away with it if it was just a media server stuck in a cupboard? I have various old cpus and motherboards kicking about which I could turn into a 24/7 media sever of some sorts and I guess the lower the power consumption the better. I would just want it to host all my music files and perhaps act as a central backup for general file serving. At what cpu speed does this become impractical or will it always be limited by the network speed or other factors?
 
not sure on that, however i have mine down at 1.4 ghz with server 2003 and a vm with TVersty on using 1 cpu and 1 gig of ram, works fine even when downloading torrents and playing a movie that needs converting (on the fly)

tho my machine still runs @ about 45 -50 degrees c (very poor air flow under my bed)
 
What minimum cpu speed could you get away with it if it was just a media server stuck in a cupboard? I have various old cpus and motherboards kicking about which I could turn into a 24/7 media sever of some sorts and I guess the lower the power consumption the better. I would just want it to host all my music files and perhaps act as a central backup for general file serving. At what cpu speed does this become impractical or will it always be limited by the network speed or other factors?

A modern cpu won't struggle at all, your HDD will always be your weakest link for streaming files. Playing the media is obviously a different story, but even so I'd wager some dosh on a 1Ghz Athlon being more than enough. :D

I dropped my dual core Athlon from 2.6 to 1.5GHz to test and noticed no difference in Windows and desktop tasks.
 
Still dont understand why people care about power consumption..

You're either very young (oblivious) or very old (not willing to conform).

I'm far from being a GreenPeace member but my trading machine needs to be on 24/7.

Thus I want a quiet (read silent), cool running PC. That ultimately means I need low power, the added bonus is I can run it for a few pence a week and not worry about it.

Heat is wasted energy, your power churning PC isn't very effecient, my little AMD is. :p
 
You're either very young (oblivious) or very old (not willing to conform).

I'm far from being a GreenPeace member but my trading machine needs to be on 24/7.

Thus I want a quiet (read silent), cool running PC. That ultimately means I need low power, the added bonus is I can run it for a few pence a week and not worry about it.

Heat is wasted energy, your power churning PC isn't very effecient, my little AMD is. :p

Well you are right, i am young (early 20's).
But im not on a great wage, infact im doing some awful work experience atm, so money doesnt come around often, and i completely understand were you are coming from but i do feel people are just doing it for the sake nowadays, to save £10 a year?
Imho its not worth the effort.

Although you seem to have a decent enough excuse :)

Also because of my computer i dont use my central heating ;)

Why do you close your fridge door?
My food would go off?
 
If your pc is on 24/7 it's more that £10 a year.
And it's less effort that OC'ing a pc.
It's cheaper too, due to not needing expensive fans and HS's
Another advantage is you have access to all the smaller AV style cases (High WAF*)

An average gaming pc uses say 450w for 3h a day and 175 for the other 21 if left on. (5kw/day)
That about £180 a year @10kWh

Even if you switch it off at night for 10h thats still 3kw/day - £113 per year

Edleake used £22 a year and it's on 24/7

Edit: WAF - wife / GF acceptance factor ;)
 
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Well i can understand if its on 24/7 etc.
But i do think theres a point when you can care too much though.

But i still believe these green protestors have penetrated the computer society!
O god..
 
Even when overclocking I always try to keep the noise level down, my pc is in my room and I like to be able to hear myself think or be able to sleep when the PC is on.

There was a time when I was younger that I would overclock to the max whatever it takes but as cheap as possible, so just throw in loads of fans and loads of RPM. Even considered buying a delta fan and using it full load!

Glad Ive matured now though to know that you can still overclock well and keep the number of fans down and use low RPM. I just cant stand any noise now, especially the high pitched whine of some hard drives or the 80mm fans, cant stand them at all!

Done a bungie mod to keep hard drive noise down, and use the lowest volts possible on all my fans. Even my CPU fan is set at 1000RPM which just about makes it inaudible. The traffic outside my window is now louder even with the double glazed window closed!

So if your undervolting to keep the noise down, then thats a good enough reason! However you might be surprised how far you can actually OVERclock with that exact same noise level!
 
I'm doing it for three reasons, noise, heat and power use. :)

I like the fact the cpu is currently running at room temp, that's pretty cool (literally). :D
 
The whole system is consuming less than 25W in general use (tested at the wall socket)
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 :confused:

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.

The lowest wattage I've managed to get is with the E8400 system which idles about 45-50watts and loads around 70-85watts (prime small FFTs + 3D-Graphics).

CPU temps range from 29°C idle to 34°C Full Prime Small FFTs load and 40°C full 50 IBT loops load!

e8400ulv.gif


He was thinking of starting a sub 100w@load club
Heh yes I was although I felt it would have like two or three members due to most people wanting a power-hungry GPU for gaming so until AMD or nVidia release a ULV 8800GT class GPU it's just me! :o

I think the ULV movement will pick up momentum in the future until it becomes as popular as overclocking (which is still a pretty small community!)

Little Bit Off-Topic

"Don't shoot me, I'm just the messenger!"

Still dont understand why people care about power consumption..
Still don't understand why people don't care about power consumption..

I guess some people just don't know where electricty comes from and therefore treat it like an infinite resource, it's not like world power is gonna run out any time soon right?, then again we may be on the brink of a global energy crisis!!!

The problem is:
  • Rapidly Increasing Global Population
  • Rapidly Decreasing Natural Resources
i.e there are more and more people with less and less resources to go around . . .

Arithmetic, Population and Energy (part 1 of 8)
"The Greatest Shortcoming of the Human Race is our Inablility to Understand The Exponential Function"

Devil's Advocate said:
Dude! this is an overclocking forum WTF you talking about all this stuff for?
Because It's interesting and relevant to all of us, the more people that start thinking for themselves and realising that they may be running a power inefficient computer/household/lifestyle then the sooner we can get more brains working on various solutions! :cool:
 
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