Power Consumption
Up until this point we’ve established that Intel’s Core i7 920 overclocked to 3.8 GHz is faster than an overclocked Phenom II X4 940 almost across the board. It’s also more expensive, due to its motherboard and DDR3 memory requirement. But where do the two platforms fall with regards to power when overclocked?


At idle, there is no contest. Cool’n’Quiet spins the Phenom II down to about 800 MHz at the Windows Vista Balanced setting. As a result, the entire platforms hovers right around 175 W of power consumption. Enhanced SpeedStep technology isn’t quite as friendly to the Core i7, and we still saw speeds around 1.6 GHz at idle. As a result, the i7 920 build never dropped below 255 W at idle.
Crank up the load, however, and simple math starts working against the Phenom II, as its elevated voltage results in higher power consumption. The gap that existed at idle is gone, and now the 3.64 GHz chip is chewing up 10 more watts than the Core i7 does.
Bear in mind that, most of the time, your system will likely be idling. So overall, the Phenom II is going to be the lower-power solution. However, when the rubber hits the road, it’s just as power-hungry as Intel’s i7, even in light of AMD’s new 45 nm process.
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When the Phenom dropped to 800mhz at idle, was the voltage also lowered or was that still running at 1.6 volts? Same question for the Core i7 too.
wouldnt it have been better for both CPU's to have been run @ 3.6Ghz, as this was the Phenom 2's sweet spot, keepin them equal.
also, as the I7 can run on Dual channel memory also, u should have run both systems @ dual channel with 4Gb of RAM to keep things equal,
if these changes were done, i believe that the i7 would have still beat the Phenom 2, but i dont think the gap would have been so high.
as for the Hyperthreadin, is there any way to turn them off, as i believe that this is what gives the core i 7 the advantage on some of the app tests.
having these settings and benchmarks are great to see what they are capable of when set to full, but i and others would like to see both chips perform side by side with exact seetings as each other, this will give us a true sight of what the Phenom 2 architecture is capable of doin against an intel chip without the fancy extras.
Did seem very strange to use only 4G of RAM for AMD chip and 6G for i7. Would have been nice to see them both using 4G and seeing how close they were then. Reckon i7 would still of been quicker though. AMD needs to hope it's AM3 platform can close the gap, because at this moment Intel are way ahead in the performance stakes.
Why are people worrying that the tests were not 'equal'?
The point of them (in part) is to show how one has an advantage over the other. The Intel costs more, but you get more for it - the question is how much.
huh, so you just upped the multi and voltage on the amd system?? I have this weird feeling that there are other settings as well to tweak...
And until Core i7 has mainstream parts I don't know of a single enthusiast who's running their system anything other than triple channel anyway, so you can't get 4GB on the i7. Giving the Phenom 2x2GB and 2x1GB would take it up to 6GB and still maintain Dual Channel if you really want to match RAM sizes (or run both at 3GB with 2x1GB and 2x512MB on the Phenom).
could the shoddy CPU cooler for the AMD system possibly be behind hte really poor overclock????the intel setup get possibly hte best cooler on the market, one that is AM2 compatible i might add so no reason not to use it for both.
Wouldve been better if they used the DFI 790FX/SB750 mobo instead of the Asus, i hear it has problems wit overclocking.
actually u will find that the i7 is capable if running in dual channel.
i know the i7 is alot better than any thing on the market ATM, but i myself and most other people would like to see a true comparison, where everything is truely equal see who is the tru winner.
i believe that if these extra settings that Intel have on there chips were to be disabled, then there wont be so much of a difference in the benchmarks.
some of the biggest differences could be claimed as the i7 was overclocked higher.
well put them to gether with the same overclock and see them perform head to head in a true clock for clock shoot out.
other factors could be tributed to the extra thread processin by the hyperthreading of the i7, dissable this to allow for a true quad shoot ot with a gain the same overclock.
if this was to be done, i also believe that it will close a lot of arguments out there, whether the i7 is etter for the fact that it is a better chip, or wether the extra features are a contribution.
im not knocking Intels new flag chip, but i believe that if u realy want a true comparison, then show what they are capable of on the same turf, and then allow for the true pedigree of both chips to shine through with what the are capable of on there own turf.
I personally would like to see this, as the architecture is supposedly the same, lets see what true differences there are in the architecture,
I would also like to see a true side by side comparison. And i think AMD could have gone higher with a better air cooler.
Really strange conclusion drawn here. Conclusions like:
"sacrifice a bit of speed" and "handle every task nearly as well as i7 does" are in my opinion, totally WRONG. The i7 crushes almost everything the 940 does, except for maybe one case or two.
Further on, the real world gaming examples given here are mainly GPU-bound and shows nothing of the potential availible in the i7. Running graphics settings at "very high" does not show differences in CPU speed and thats why results are equal between the CPU.
Actually you do say that "Intel’s Core i7 920 overclocked to 3.8 GHz simply delivers the most compelling experience".
Even here you contradict the quotes on top. And I also believe the non-overclocked i7 would deliver the most compelling experience.
Ive read many reviews on the CPU doing exactly the same errors performed here. For a GOOD review of the CPU I would recommend.
http://www.hardocp.com/article.htm [...] RodXNpYXN0
Comparing games at 640 resolution gives a much better hint of non GPU-bound performance
/AMD x2 3800+ user
I am sorry that u dont feel that what has been stated is correct or feesable, but to call me an AMD fanboy, is disrispectfull, as i currently own an Intel Q6600.
i go where the best performance and price comes into factor.
i just think that if ur going to compare 2 CPU's, show what they are capable of, then show what they are on the same terms, this will truely show what the differences are between the 2 cores which is what has dragged up debate since intel announced the design features of the i7.
i would just like to see the 2 cores battle it out on a so called even score, where the 2 cores can shine without fancy features.
but in the long run i know the full features of any CPU or any component is what matters and also will determine the sale.
What this proves is one of intels slowest i7s is still better than AMDs newest and best of the best.
I heard in 2-3 years time AMD will move from AM2+ and AM3 sockets to a new one (which will need a new cpu and new motherboard), based on that it would be better for current Intel owners to stick with core2 duos and get the i7 as either way they will need to buy a new motherboard etc and i7 is better than AMD.
In the old days AMD where great i have an old Athlon 2500 XP and 6 years ago that thing beat Intels Pentium versions, Its a pity AMD lost its way with the current set of cpus.
Core i7 entry CPU beats the best Phenom II !! Intel is definitely the winner. And the price difference is fair from a value point of view. Besides; applications are, and always were, more optimized for intel processors, which I consider an advantage for intel.
Chris: I think the games' benchmarks should have been run on lower resolutions to shift the bottleneck from the GPU to the CPU to further demonstrate core i7's lead.(Especially in Crysis)
For those who demand clocking both CPUs @ the same clock and using dual channel memory for both: It's not a comparison of clock to clock performance (though the performance gain of core i7 is larger than the clock difference which means its c2c performance is better), its a comparison of the maximum perf. you can get from the 2 systems putting in mind current prices and upgradibility. And the article has made everything clear. Good job, Chris.
Did seem very strange to use only 4G of RAM for AMD chip and 6G for i7. Would have been nice to see them both using 4G and seeing how close they were then.
Do you honestly think the 6gb ram had a real advantage over the 4gb in performance? Even Crysis doesn't use the extra 2gb!! What's really beneficial here is the triple channel bandwith. How much exactly the 3rd channel is adding to overall performance is still unknown to me and many readers, I believe we need a dual channel vs triple channel benchmarking!
please stop being so lazy and put the prices in £.
I would have thought the comparison was completely fair - take two chips, overclock them as far as they are stable then run some benchmrks, cant get much fairer than that.
Someone suggested disabling hyperthreading in the i7, a better idea would be to enable it on the phenomII - wait it doesnt have it..... thats like saying my ferraris better than your lambhorghini, so ill run it with 3 wheels just to give you a chance... pointless.
actually, ive just read the setup and the i7 wasnt even clocked as far as it would go! if they kept it at 4ghz (which they did achieve) and ran teh settings again, the difference would surely have been even greater.
I feel like the conclusion was written by someone who is trying to think of ANYTHING he can to give AMD an edge, even though the facts speak for themselves. The intel proc decimates the AMD proc, and the price difference is crap. As for the people who want half the features of the Core i7 turned off to make it equal - are you nuts? What do you think you're paying for when you buy a Core i7? You're not going to turn everything off and run it cripled... you're going to unleash the power of the machine. if you have a problem with price, wait an extra 2 weeks for a paycheck and bump down to 3GB of ram. I'm a huge AMD fan, but AMD is getting rocked. They need to wake up and release something worth buying.
I'm a huge AMD fan, but AMD is getting rocked. They really need to release something worth buying, but unlike what the author would suggest - this isn't it. The phenom II isn't worth putting in a new rig, not at a 250.00 price dif. You're talking about Old technology, DDR2. Wouldn't it make more sense to drop down to 3GB of ram and eat top roman for a week, instead of buy something that will be gone tomorrow? Like I said, HUGE AMD fan here; and I know many of you AMD fans want to defend it to the bitter end - "Turn off hyper threading, run 4 gb or ram... blah blah blah" - but let's not kid ourselves... Are you really going to run the processor in crippy-mode when you buy one? No way...