C't magazine: Best low power platforms

jojo4u · Post by **jojo4u** » Fri Jun 11, 2004 5:37 am

German magazine C't did an interesting comparism back in march (issue 06/04).
They took:
Pentium-M
VIA-C3
Celeron Tualatin 1200Mhz
Athlon XP-M, Thorton, Barton, T-Bred
P4
Athlon 64
and put dem into suitable boards. Then they compared them in terms of performance and power draw.
Since the article is huge, I will concentrate on the silent information.
Figures of the style xx/yyW mean idle/load. All power figures are AC and include PSU, CPU, mobo, 512Mbyte RAM, VGA, Hdd.
idle = Win XP Desktop
load = 3DMark 2001

Here is the table that is presented as picture below.
I divided the table in 3 performance groups. The groups themselves are sorted after power draw.

Pentium-M
On Lippert Thunderbird. on-bard VGA, no AGP, PCI only 3,3V. This board is primary for industrial applications.
Simply the best low-power CPU today. Can't wait to use it on a desktop.

Celeron Tualatin and VIA C3
On Asus TUSL2. on-board VGA. The Celeron is ~1,5x faster.
Tualatin and C3 on TUSL2 need too much power.
The Celeron is a leakage current monster.
C3 only an option if it's speed is really enough for you. Best Ahtlon XP setup only needs 14/22W more.

Athlon XP-M, Barton, Thorton, T-Bred-B on Aopen AK79D-400VN
The T-Bred-B need some 10% extra compared to the other three.
The XP-M has no advantages to an undervolted Barton/Thorton.
Linux (Fedora 1) needs ~10W more at idle.
Disabled Disconnect sucks 30% more.
Best low-cost CPU to built a low-power system

Athlon 64
Much leakage current here. Look at the 800Mhz figures.
But still the best choice today if you look for a general purpose PC.

P4-E
No comment.

Additional findings:

They compared several PSU on the Celeron TUSL2 platform in idle mode:
Enermax 433W: 59W
Tagan 380W: 56W
200W Delta/220W Aopen-Barebone: 53W
90W Travla: 48W

Rise of power draw of AGP-VGA compared to the onboard VGA of the C3 TUSL2 platform:
A Radeon 9600 needs 4/14W more
A Nvidia 5950 needs 24/89W more (!!)
The Radeon needs 2-3W more compared to the Nvidia 5200.

Pentium-M 1,6Ghz platform with Morex 60W
Zoomplayer 3.31 DivX 5.1.1 playback: 46W
Media Player 9 DivX 5.1.1 playback: 39W

DVD playback by WinDVD 4 with Morex 60W
P-M 1,6: 30W
P-M 1,1: 26W

sgtpokey · Post by **sgtpokey** » Fri Jun 11, 2004 8:37 am

Very good find!

By the way:

Pentium-M 1,6Ghz
Zoomplayer 3.31 DivX 5.1.1 playback: 46W
Media Player 9 DivX 5.1.1 playback: 39W

DVD playback with WinDVD 4:
P-M 1,6: 30W
P-M 1,1: 26W

I assume this is the total power draw of the system, and not the power draw of the cpu-only?

I assume this since they note that the Petium M is the "best low-power cpu today" that wattage quoted above is most likely the total power draw of the system.

jojo4u · Post by **jojo4u** » Fri Jun 11, 2004 9:28 am

sgtpokey wrote:
Pentium-M 1,6Ghz
Zoomplayer 3.31 DivX 5.1.1 playback: 46W
Media Player 9 DivX 5.1.1 playback: 39W

DVD playback with WinDVD 4:
P-M 1,6: 30W
P-M 1,1: 26W
I assume this is the total power draw of the system, and not the power draw of the cpu-only?

It's the whole system, like all power figures in my post are.

Post by **MikeC** » Fri Jun 11, 2004 12:36 pm

Another good find, jojo4u! It's just the kind of thing we'd do here. Makes me wish I could read German.

jojo4u · Post by **jojo4u** » Fri Jun 11, 2004 1:15 pm

MikeC wrote:Another good find, jojo4u! It's just the kind of thing we'd do here. Makes me wish I could read German.

I just decided not just to lurk before the PC but give the community something back.
About Germay:
I believe the Germans are more behind sustainability. Paired with German engineering the result is that there at least the same silent solutions compared to the USA with ~3,5 times the inhabitants.
Just one example: Pc-Cooling.de offers three different fanless PSU at the moment. On top, there are 3 other fanless 300W+ PSU available in Germany.

Jan Kivar · Post by **Jan Kivar** » Sun Jun 13, 2004 12:06 am

jojo4u, can You provide a link to the article/tests, provided they are on-line and free of charge?

If not, does the article list what motherboards were used on the testbeds?

Cheers,

Jan

jojo4u · Post by **jojo4u** » Sun Jun 13, 2004 2:20 am

Jan Kivar wrote:jojo4u, can You provide a link to the article/tests, provided they are on-line and free of charge?

If not, does the article list what motherboards were used on the testbeds?

It's a print magazine. The articles are available online for a few bucks. So no link here...
The motherboards:
Lippert Thunderbird for Pentium-M
Epia M1000 for C3
Asus TUSL2 for C3 and Intel Celeron Tualatin 1200
Aopen AK79D-400VN for Athlon XP
Intel D875PBZ for P4-E 3,2
HP-Desktop D530 SFF for P4-E 3,0
Fujitsu-Siemens D1607 for Athlon 64

So there must be one correction made: the figures for the P4-E 3,0 are with the 220W power supply of the HP D530 SFF.

ist.martin · Post by **ist.martin** » Mon Jun 14, 2004 9:43 am

That's great info. I hadn't realized that the 1.6MHz Pentium M is power equivalent to a VIA M10000 setup.

What a perfect candidate the Pentium M is for a Scythe Otanashi silent case! The Scythe case works very well cooling the VIA M10000, so it should provide comparable cooling for the Pentium M.

That would be a superb silent system for all but gamers. Couple it with a 4 GB internal flash drive for the OS, browser, mail client and office programs, and you would get a high-performance 0 dB system with no moving parts. Add on a low-noise external HDD for occasional use programs and files, and it would be a 0 dB system that is practical for a huge percentage of users.

aidanjm2004 · Post by **aidanjm2004** » Sat Jul 03, 2004 6:45 pm

jojo4u wrote:Athlon 64
Much leakage current here. Look at the 800Mhz figures.
But still the best choice today if you look for a general purpose PC.

The Athlon 64 numbers look a bit fishy. How can it be using that much power, at 800 Mhz? Would you mind explaining what you mean by "current leakage", BTW?

silvervarg · Post by **silvervarg** » Mon Jul 05, 2004 2:38 am

ist.martin:
That's great info. I hadn't realized that the 1.6MHz Pentium M is power equivalent to a VIA M10000 setup.

Note that they use different motherboards. That can make a substantial difference. Especially since the Pentium-M used an industrial board. These boards are typically very expensive, so they are not a practical option for most computer builds.
4GB internal flash drives are very nice, but not very economical at the moment, and 4GB is very little even for every day usage. However it can be practically used so your harddrive can be spun down 99% of the time.

ist.martin · Post by **ist.martin** » Mon Jul 05, 2004 7:22 am

silvervarg wrote: 4GB internal flash drives are very nice, but not very economical at the moment, and 4GB is very little even for every day usage. However it can be practically used so your harddrive can be spun down 99% of the time.

I am getting by right now with just a $50 800 MB IDE Flash drive. It has 98 SE installed, with the latest IE, Outlook Express, Acrobat, Media Player and Flash. It leaves me about 160 MB of free hard drive space, and allows me to use the web/email for 5-8 hours daily in TOTAL SILENCE.

I plan to get an external USB harddrive where I will install infrequently used programs, including an Office compatible suite. But right now, for about 99% of what I need, the current system is perfect. And the absolute silence is a dream.

FWIW - my system came by way of http://www.peacefulpc.com/ - I bought one of his test systems off of eBay. The totally silent Scythe, Flash IDE and VIA M10000 with 98SE really is a great combo. I've had at least a dozen envious folks in my office thinking I paid up big for my 0 dB 'wonder' system

jojo4u · Post by **jojo4u** » Mon Jul 05, 2004 11:00 am

aidanjm2004 wrote: The Athlon 64 numbers look a bit fishy. How can it be using that much power, at 800 Mhz? Would you mind explaining what you mean by "current leakage", BTW?

First read: http://www.xbitlabs.com/articles/editor ... ocess.html

How could it be that the Athlon 64 at 800 Mhz needs 10W at idle more compared to a Thorton at 1350Mhz?

Btw, I am assuming that the leakage power is affected by the clock speed. Has anyone a source explaining this?

Let's look at the datasheets:

AMD Athlon 64 old revision
2 GHz: StpGnt current 32A @ 1,50V = 48W
0,8 Ghz: StpGnt current 10A @ 1,3V = 13W
Voltage reductions are going into the equation quadrated (did not find the englisch word), clock speed reduction are going linear into the equation.
doing the math: 48W * (1,3V/1,5V)^2 * 0,8Ghz/2Ghz = 14W
so the numbers are fitting

Athlon XP "Thorton" 2400+
2 GHz: StpGnt current: 9A @ 1,65V = 15W
now the math for 1,35 Ghz @ 1,35V
15W * (1,35V/1,65V)^2 * 1,35Ghz/2Ghz = 6W

So our Thorton only needs 6W compared to the Athlon 64 with 13W.
This are 7W more. Now divide by 0,7 for the PSU efficiency and you are at 10W. Note: I did no number magic here, they fitted at the first try.

sources:
http://www.amd.com/us-en/assets/content ... /27375.pdf

http://www.amd.com/us-en/assets/content ... /30430.pdf

peacefulpc · Post by **peacefulpc** » Mon Jul 05, 2004 12:01 pm

ist.martin wrote: FWIW - my system came by way of http://www.peacefulpc.com/ - I bought one of his test systems off of eBay. The totally silent Scythe, Flash IDE and VIA M10000 with 98SE really is a great combo. I've had at least a dozen envious folks in my office thinking I paid up big for my 0 dB 'wonder' system

thank you, glad you liked the system!

they aren't for everyone, or every situation, but at 0 db, it makes a great little workstation, or front end for a powerful computer in the basement.

C't magazine: Best low power platforms

C't magazine: Best low power platforms

Pentium-M is clearly a candiate for a Scythe silent case

Re: C't magazine: Best low power platforms

800 MB

Re: C't magazine: Best low power platforms

Re: 800 MB