What modern processor uses the least amount of power?

[eflat]

I am building NAS server but do not want to base it around some old Pentium III or something to save power.

The best I have seen so far is the Celeron, which Newegg says uses 35 watts.

Anything better out there?

 

[harpoon84]

I take it you mean a desktop CPU?

45nm C2Ds (E8x00 series) consume very little power. Around 3W idle, 30W under load

 

[nanaki333]

the conroe celeron's use 35w of power and the a64 x2 BE series use 45w.

 

[Tempered81]

Originally posted by: harpoon84
I take it you mean a desktop CPU?

45nm C2Ds (E8x00 series) consume very little power. Around 3W idle, 30W under load

undervolt & underclock it maybe 2-20watts

 

[nanaki333]

Originally posted by: harpoon84
I take it you mean a desktop CPU?

45nm C2Ds (E8x00 series) consume very little power. Around 3W idle, 30W under load

mmmm.. i didn't know the wolfies were THAT low. i guess depending on the budget, that'd definitely be the finer choice

 

[Idontcare]

Originally posted by: jaredpace

Originally posted by: harpoon84
I take it you mean a desktop CPU?

45nm C2Ds (E8x00 series) consume very little power. Around 3W idle, 30W under load

undervolt & underclock it maybe 2-20watts

Maybe even less than that. With the 333MHz FSB, you could really set the multi down to minimum (6X is it?) and drop that FSB like crazy (power reduction for NB) and have a nice 1.5GHz chip or thereabouts with a Vcore most likely at or under 1.0V.

I know I was able to take my B3 QX6700 Kentsfield low enough in frequency and FSB that it was smallFFT stable at 0.90625 Vcore. Can't remember the freq though, it was just some tests playing around to see how low it could go.

Can't imagine what you could do with a 45nm Wolfdale. Your hard-drive will be consuming more power than the CPU :Q

 

[Modelworks]

http://clubit.com/product_detail.cfm?itemno=A4842001
60.00

Via is not a cpu for people wanting gaming, etc.
But for a nas box or home server I don't think it can be beat at that price.
I love it.

And power usage is way below anything else out there.
Its been one of the things via is using as its selling point.
12W under full load.

Toss some ram on the board and its ready to boot.

 

[robmurphy]

The celeron single core CPU does not have the speedstep feature. This means it runs at full power all the time. The new dual core celeron does have the speedstep feature though, as do the dual core pentiums chips based on the C2D. I think you will find the dual core with speedstep will use less power when idle than the single core.

AMD has several low power single core semprons/athlons that support the AMD cool'n'quiet software. I use this on all my AMD desktops. I upgraded the CPU in one of them from a Sempron 3400+ which did not support cool'n'quiet to a dual core 4600+. The idle power of the system was reduced about 25% after adding the dual core CPU.

I have not used Intel's speedstep but the AMD cool'n'quiet works very well on XP and it is available on Linux. You also need to remember that its the power consuption of the whole system that matters, not just the CPU. Usualy AMD systems used less power overall than
intel ones, but I think that is changing.

For really low power maybe you should checkout some of the VIA offerings.

Rob

 

[nanaki333]

anybody ever heard of amd geode?

http://www.newegg.com/Product/...x?Item=N82E16813130103

no time to google, but just thought i'd throw it up. maybe i won't have to google when i get back



looks like the via c7 eden is the best cpu for lower power consumption. it uses 1W at max load.

 

[kalster]

geode's are pretty good , i use a geode 266mhz SBC (single board computer) for my voip server, it works pretty well, they are derived out of sempron's i think, not the fastest but for embedded applications they are good, if you want to get a regular pc case, then i would recommend the low power athlons (be series) or the intel celeron's

 

[eflat]

Originally posted by: harpoon84
I take it you mean a desktop CPU?

45nm C2Ds (E8x00 series) consume very little power. Around 3W idle, 30W under load

Wow that is awesome. Finally it looks possible to build a desktop with the power consumption of a Laptop.

 

[myocardia]

Originally posted by: CitizenDoug
Wow that is awesome. Finally it looks possible to build a desktop with the power consumption of a Laptop.

Actually, it's possible to do alot more than that. This is what I use the majority of the time now, unless I feel like gaming. That's an actual laptop processor. Oh, and here is a comparison between the D201GLY and the Via C7 that's on this motherboard.

 

[Tempered81]

heres a core2duo that uses 10 watts under load.

http://www.pclaunches.com/proc...voltage_processors.php

its santa rosa based, and uses a mobile platform. Still not bad for a 533mhz bus, with 1.2ghz and only using 9-10 watts on full load.

 

[VirtualLarry]

Originally posted by: robmurphy
The celeron single core CPU does not have the speedstep feature. This means it runs at full power all the time. The new dual core celeron does have the speedstep feature though, as do the dual core pentiums chips based on the C2D. I think you will find the dual core with speedstep will use less power when idle than the single core.

AMD has several low power single core semprons/athlons that support the AMD cool'n'quiet software. I use this on all my AMD desktops. I upgraded the CPU in one of them from a Sempron 3400+ which did not support cool'n'quiet to a dual core 4600+. The idle power of the system was reduced about 25% after adding the dual core CPU.

I have not used Intel's speedstep but the AMD cool'n'quiet works very well on XP and it is available on Linux. You also need to remember that its the power consuption of the whole system that matters, not just the CPU. Usualy AMD systems used less power overall than
intel ones, but I think that is changing.

For really low power maybe you should checkout some of the VIA offerings.

Rob

I'm pretty sure that Celeron C2D chips all support SpeedStep and C1E.

 

[robmurphy]

The 420, 430, and 440 Celerons do not support speedstep. Check Intel's website.

The dual core E1200 does support speedstep.

All the Celerons I mentioned support C1E.

 

[pm]

If you were thinking about a Pentium 3, then I'd offer the Intel D201GLY2 for consideration.
It runs passively, no fans (although the power supply needs a fan to keep air moving). Total system power is under 40W - that's everything, including the power supply.
The motherboard + video + LAN + CPU costs less than $75.

A review:
http://www.silentpcreview.com/article780-page3.html
Another review which compares power consumption and benchmarks vs. a Via Epia 1.5GHz CPU
http://resources.mini-box.com/...power-consumption.html

 

[mindless1]

There are lots of ways to end up under 20W, under 10W at idle and then the board and drives are a larger % of power consumption.

Even picking processors that aren't particularly power miserly, with a decent board having the full compliment of over/underclocking settings including low vcore adjustment you can underclock most to surprisingly low power consumption, and a NAS doesn't need much at all in the way of CPU performance unless it were some kind of soft-RAID other than 0 or 1. CPU power is rated based on stock speed operation while you have the ability to go beneath that when underclocking, especially reducing voltage. Granted that's ignoring other power reduction features but for a NAS it's not so important to have those other power reduction features if you can just underclock and undervolt in the first place as there is not going to be a bottleneck for typical NAS functionality (but you haven't mentioned yet if you wanna run a DNS/mail/FTP/proxy/kitchen-sink like some people do).


I suggest you focus instead on the motherboard you want to use as there are variations in chipset power consumption, chipset performance (Via PCI bus = PITA), physical size and features per size, cost, manufacturer general quality and support. Just avoiding a separate video card can make more of a power difference, and choosing DDR2 based board makes memory cheaper (though for limited # of clients you don't need much memory).

Once you've settled on the board, get the complimentary CPU for it. There's not much need to spend a lot on a NAS, many people use the old P3 platforms merely because it not only does the job but is cheap if not free because they already have many if not all the parts already.

 

[eflat]

How about video cards? I assume built in is going to be the most efficient, but are there any pci express cards?

The reason I ask this is because I already have a motherboard and memory, and it uses the 775 cpu socket

 

[harpoon84]

Originally posted by: CitizenDoug
How about video cards? I assume built in is going to be the most efficient, but are there any pci express cards?

The reason I ask this is because I already have a motherboard and memory, and it uses the 775 cpu socket

Yeah, IGPs would be the most power efficient, although there are ways to cut down power usage on dedicated graphics cards too.

For example, my 8800GTS 320 stock clocks are 513MHz core, 792MHz memory. I've set profiles in ATI Tool so that when on desktop, it's underclocked to 113MHz core/140MHz memory. This is as low as it goes without graphical artifacts. When I run games, it automatically overclocks the card to 660MHz core, 1060MHz memory. That way, I get the best of both worlds - lower power consumption when I'm doing 2D stuff, and extra performance when I really need it, playing games.

 

[superstition]

Also consider performance per watt. The ideal part is one where you get the best performance per watt. If it takes you 10 times longer to do something, like render a video with a processor that consumes 50% less energy, then you're wasting power.

ATI's 38xx series GPUs have been purchased by some because they "consume less power". But, they actually have worse power consumption if you look at their performance per watt as compared to an 88xx Nvidia part. This is particularly bad because the ATI chips are made with a smaller process.

However, if you're running a machine that never has much CPU load, like some servers, then it makes more sense to look at total wattage first.

 

[mindless1]

Originally posted by: superstition
Also consider performance per watt. The ideal part is one where you get the best performance per watt. If it takes you 10 times longer to do something, like render a video with a processor that consumes 50% less energy, then you're wasting power.

ATI's 38xx series GPUs have been purchased by some because they "consume less power". But, they actually have worse power consumption if you look at their performance per watt as compared to an 88xx Nvidia part. This is particularly bad because the ATI chips are made with a smaller process.

However, if you're running a machine that never has much CPU load, like some servers, then it makes more sense to look at total wattage first.

Yes, a home server has very minimal processor requirements so performance per watt won't be a factor. Even a 500MHz Celeron won't be at half load. Similarly the goal for the video card wouldn't be anything "performance" oriented, an old PCI RageXL card (same chip integrated onto many server motherboards) would suffice and is cooler running, less power consuming than anything modern with the exception of some integrated video.

 

[WhoBeDaPlaya]

Originally posted by: kalster
geode's are pretty good , i use a geode 266mhz SBC (single board computer) for my voip server, it works pretty well, they are derived out of sempron's i think, not the fastest but for embedded applications they are good, if you want to get a regular pc case, then i would recommend the low power athlons (be series) or the intel celeron's

Ouch, reading this makes me feel guilty. I've got an OC'ed E6400 (3.3GHz) as my VOIP server Granted, that's not its only function but still...