This report stirred quite a contraversy in the PC enthusiasts world.
However, many people raised objections to the accuracy of measurement tecnique using power at wall. They cite AC-DC converter inefficiency, on-board DC-DC convertor inefficiency, possibly different power consumption of mismatching components, etc.

To eliminate this kind of objections, I am proposing an improvement to "the wall measurement technique". It is possible to measure the conversion factor of each individual system. To do this, you need to calibrate the consumption right at the processor socket by measuring the difference in overall power consumption between the normal operation mode (whatever the test is) and the power in the same but with a known resistor connected to the CPU core voltage rails.

If the "calibration" resistor is, say, 1 Ohm, it should cause 1.5W increase in
"raw processor power" (I assume 1.5V core Vcc). Due to limited efficiency of DC-DC convertor and ATX PS, the wall power increase is expected to be higher, about 1.5/0.9/0.8 = 2.08W
The difference between two actual measuremnts will give you compound efficiency of the test system.

The "calibration" will require to solder down two thick wires to each motherboard, preferrably right to legs of core voltage electrolytic caps. The whole measurement technique "at wall" is better to be calibrated as well, by checking with a big-ass resistor of proper value (in place of the PC).

Best regards and good luck,

- Alexei Predtetchenski, aka "aap"

Too many posts, jumping in late here, so I won't respond to any individual one. Just a couple observations:

1) The 90nm processor runs at a lower voltage than the 130nm. That alone is probably responsible for almost the entire power savings. It would be interesting to over-volt the 90, or under-volt the 130 (or maybe meet in the middle) to see how the power usage compared. It would be interesting to see if you could get most of the benefit by just under-volting existing 130nm processors.

2) Even though AMD's process appears fine for making slower chips, hence starting with lower-end chips, that says nothing about how good it is at ramping. The troubling clue here is that they have introduced no higher-speed chips on 90nm, but have thrown out a bunch of lower-speed chips. This is the same game Intel played at the beginning; you could only buy the highest speed P4s as Northwoods. This is an indication that AMD's 90nm process is not yet perfect, and is facing some of the same issues. The offshoot of this is that, in spite of the power usage shown here, 90nm chips might not make very good overclockers.

3) The days of easy speed gains are over. We just are not going to see the big steps up that we used to see in the past. We need to remember this when evaluating potential. Processors speed bumps are going to become smaller and smaller as they continue to get more complex. This isn't an Intel problem or an AMD problem. It's a problem of physics. Until they invent a new way to make chips, we're going to have to look for more creative ways to make new advances (hence the sudden interest in dual-core chips).

One thging to note, in the past Intel has used a copy exact and shrink when using new smaller processes, and with that last few revisions AMD has added features with their die shrinks. This time it is the exact opposite. congrats to AMD for pursuing a process that is proven to work. It is a measure of AMD's recent success that Intel has felt the need to go outside of their normal bounds to compete. 65nm should be really interesting, electrical leakage with smaller processes has become a definite issue, when comparting the older P3 to the Prescott core total watts of consumption is a definite apples to oranges comparasion. If you somehow managed to more than double the transistorsof the old P3, and pushed the speeds to even the A64 levels yopu would see a huge difference in power draw.

Wow. I guess throttling should be enabled on desktop chips too. 112Watts at idle is a pretty ridiculous waste if you ask me.

112Watts at idle?!?! A Pentium III 800 at full blast uses 20.8 Watts and a Low Voltage P-III 933 uses 11.61 Watts maximum.

For the home user it's a pretty bad idea to upgrade to the new generation of CPUs. It would add significantly to the electricity bill.

First off what causes amd the most trouble is thier chips tend to get slapped into realy stupid puters.

I have seen $1000 amd systems sold with 64 meg integrated vid AND a single channel pc 2700 memory.

Same with intel comes with twin channel pc 3200 memory and a pcie ati card.

We wont even get into the fact amd doesnt have enough plopping down into the 4-600 range in oem channels now. Its now dominated by celron d's.

As for celeron d and prescott remember for the mainstream buyer who still isnt gona do much all that often the chip runs cool. Its only when you push it to max that it realy gets hot.

As for duron they are popping up from wacky oddball oems in 300 buck systems sold with integrated vid and 128 megs of slow ram... lets guess how peppy they are shall we?:)

What does this say about AMD's .09 micron process vs Intels? Just as good? Better? Any process gurus out there care to comment?

Ouch :( 60W extra between idle and load?

Folding 24/7 is equivalent to leaving a lightbulb on all the time.

That costs me ...*calculator tapping noises*

Holy fkucing hsit, it's 63 quid a year!!! ($115)

Also of note, notice he said that this is the whole system measured at the WALL (110-120V AC) assuming he's in the US or (210-220V AC) if overseas. It would be helpful to know the voltage he's running at at the wall. If he's on 110 then you guys overseas will show a significant less power usage at 220V. The other numbers of Max Power useage from AMD's specs I believe are at Core voltage which is DC.

yes, but how does it overclock?

#19, these tests stressed CPU and RAM only, not the video card, which is running pretty much at idle (2D only) the whole time. Running 3dmark05 or something equally graphics-intensive would probably add another 50-60 watts to the figure.

I'm having strong suspicions that early reports of 90nm Athlon64's running hot were due to old BIOS not recognizing the new CPU, and feeding it 1.5V instead of 1.4V. It might not account for the whole difference, but likely a good part of it.

The 90nm A64 is a very hot topic (he he) amongst hardware enthusiasts, but why are there so few reviews among the top hardware sites? Are Anand & Co under NDA or are these chips just very hard to get one's hands on?

Yeah, I heard that they were going to run hotter too. This is definately good news. :)

Wow, I never realized that the Prescott consumed more than 200 watts under load.O_o

I second this! All modern A64 motherboards support Cool n Quiet so it'd be logical to include in the testing imho.

Oh I fergotm amds greatest problem... they are in debt and would have to make a gargantuan profit to realy profit from any of this any time soon. Anyhting less just pays the banks not amd.

Uh oh, Slashdot :p

edit: nevermind, I see below that you DO work in 85 degree temps. just wow. :)

Excellent. Winchester S939 3200+ here we come! :D

Actually, a Winchester 3500+ 2.2GHz sounds enterprising. And dual-cores, think of the dual cores on this sweet process.

Also, this is just another reason to buy AMD over Intel. Its not something that people think about often, but saving almost 100W for a similar system would equal a large power saving over the life of the PC.

I don't think (for Intel) its the actual 90nm process causing the heat issues for Prescotts/Noconas...Its actually due to the design of the P4 itself that's the problem.

If you look at the Athlon64 and Pentium-M (full load with power saving features OFF) both 90nm versions of these CPUs run FAR cooler than any P4/Celeron/Xeon could (they're also cooler than their older 130nm brothers)...So its not just about the manufacturing process, its architecture too. Something to think about.

And BTW, PIIIs highest is just over 30W.
(PIII-S 1.4Ghz and Celeron "Tualatin" 1.4Ghz)

Underclock them and run them at 1.054v like I do and you got yourself a fanless (passively cooled) 1Ghz CPU that craps on VIA's C3. Great for a BSD/Linux PC or for typical office stuff. As if I need 3Ghz+ to surf the web! :)

Can we say " real men can perform successful die shrinks?"

Er, weren't these chips supposed to run hotter than their 130nm counterparts?

If this info is correct it looks like AMD isn't having any problems with their transition to 90nm parts, which is definitely a good thing.

Looks good.

Looking at that data, would I be mad in assuming that a 90nm 3500+ uses around 23W in idle mode?

Assuming power supply is 75% efficient:

112W * 0.75 = 84W getting to system
179W * 0.75 = 134W (130nm under load, near TDP of 89W, let's assume 84W)

134W - 84W = 58W Mobo, Gfx, IDE, etc power consumption

84W - 58W = 26W
26W * 0.9 (motherboard VRM efficiency) = 23W

I suppose that system power usage also drops in idle mode though as well.

Yes, these figures are extremely dodgy and vague and aren't worth much more than the speculation they are.

Update: Cool'n'Quiet was not enabled on the Socket 939 motherboard.

Then it would be very nice to see results with it enabled. Glad to hear it can be even better.

Also, for idle comparison, wouldn't it be nice to have a not-so-hungry graphx card on?

Great news day with this and the Linux drivers thing.

#24, you're quite optimistic if you consider 80% PSU efficiency "typical". Manufacturers might write a lot of different figures, but the fact remains that only the very best PSUs pass 80% efficiency, and then only in a narrow load range they are optimized for - above or below that range, efficiency drops off. For example, Antec Phantom fanless PSU pushes 88% efficiency at 300W load, but only 76% at 90W and 81% at 150W. Keep in mind that this is the most efficient PSU that money can buy - a lot of money, as it retails for over $200. A more "typical" unit, such as Vantec Stealth 420W PSU maintains 69% efficiency at 370W load, and 72% at 90W load.

I could not work in an office with an ambient temp of 85F. I'd be sweating my butt off.

The power delta under full load is shocking. There is a difference of more than 80 W between the 90nm A64 system and the Prescott system at full load.

Assuming the power supply runs with 75% efficiency, that is still a 60 W difference in consumption, although the 80 W shows up on the power bill.

That will cost some significant money for a folding farm running 24/7.

Does anyone know when we'll be seeing these in large numbers in the retail channels? And what about the opterons?

This would seem to be good news for AMD. I am glad someone finally measured the power consumption, and not just the temperature of the CPU.

I am surprised that AMD is not hyping this to the press. It has been 7 or 8 days now that people have been talking about how hot the 90 nm A64's run, but with no real measure of consumption. (see the news on TR from Sept. 24).

The fact that there seems to be a significant power reduction is very positive.