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AMD FX: Energy Efficiency Compared To Eight Other CPUs

Intel CPUs: Core i5-750 And Core i5-2500K

We're also including two Core i5 processors, which are some of the most popular in our cabinet of Intel CPUs. The Core i5-750, which is based on the 45 nm Lynnfield design and employs LGA 1156, is our first contender. Second up is the Core i5-2500K, based on Intel's 32 nm Sandy Bridge architecture.

A manufacturing process generation and a number of architectural tweaks separate Lynnfield and Sandy Bridge, giving the Core i5-2500K access to significantly higher clock rates. The newer chip runs at a 3.3 GHz base clock compared to the Core i5-750's 2.66 GHz. With Turbo Boost accelerating a single core, the newer processor can speed up to 3.7 GHz, which is 500 MHz more than the i5-750.

The -2500K's data sheet reveals an impressive range of features, like AVX instruction support, hardware acceleration for AES encryption and decryption, thermal monitoring, second-gen Turbo Boost, and HD Graphics 3000 (including Quick Sync). Hits against the Core i5 include a step back on the shared L3 cache, from 8 MB down to 6 MB, and a lack of Hyper-Threading. You can read more about Sandy Bridge in: Intel’s Second-Gen Core CPUs: The Sandy Bridge Review

Bear in mind that it takes a K-series processor to enable multiplier-based overclocking in the Sandy Bridge generation. AMD is particularly proud of the fact that its entire FX series is multiplier-unlocked. However, overclocking prowess only take an architecture so far when competing products offer the same capability.

  • compton
    The low idle and load power consumption numbers of the SB K series are why I love them so much. Less power = less heat and noise, and SB is certainly worth it for me. BD, on the other hand, is just a strange bird. Someone out there could probably find a way to leverage it successfully, and that one person is going to be very happy. Maybe Bulldozer makes a lot more sense in its server configurations -- but I really wish AMD had just given the Phenom II a slight dust-off and die shrink. Everyone was pulling for AMD to do something great with BD, and the efficiency results are just abysmal. If you got great performance, but dis-proportionally high power consumption, that would be okay as well. With BD, you get the worst of both world, and not much of a saving grace. Perhaps Trinity will do something with this albatross that is BD and make it respectable, because the efficiency comparison is embarrasing.
    Reply
  • de5_Roy
    thank you tom's. this kind of article (performance-efficiency analysis) is one of my favorites. i've been waiting eagerly for an article like this from reviewer sites, tom's beat everyone else. :D
    the benchmarks with real world softwares(and not some specialized highly threaded synthetic benchmark that gives biased results) are the ones that matter to me. i use some of the softwares occassionally (blender), some more frequently (winrar, 7zip, lame encoder) and this article helped me a lot when i choose my next pc.
    did you guys see the ridiculous tdp number on cpu-z screenshot of fx8150? 223 w what the !@#$. i wonder which one got it wrong, amd or cpu-z.
    amd-fans-in-denial can argue as much as they want, but the reality didn't change. the efficiency numbers pretty much mirrored the bd review - bd isnt power efficient. even the ph ii 980 - the most power hungry of phenoms is more power efficient than fx 8150. and people who don't care about power consumption should care about the cooling and maintenance bd would need along with a power hungry high performance gfx card. imagine running an air-cooled fx 8150 @ 4.7 ghz with nvidia gtx 580 or radeon hd 6990.
    i can use any kind of acronyms like 'lol' or 'lmao' on bd's laughable power efficiency(even lynnfield beat it!) and performance but i am really sad and disappointed.
    if amd can't compete with intel, intel will keep selling their cpu at a high(and higher) price - avg users like me will be the loser.
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  • tacoslave
    everytime i read a BD article i die a little inside. Plus what we all knew would happen already started Intel already raised the K series prices a couple bucks.
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  • compton
    Geez, the 2700K is creeping up on $400. Thanks a lot AMD. You're off my Christmas list.
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  • dragonsqrrl
    comptonGeez, the 2700K is creeping up on $400. Thanks a lot AMD. You're off my Christmas list.Ya, the MSRP is $332, but the price on newegg is $370. Even for a brand new processor that's a huge premium over MSRP. It'll stabilize to the $330 price range eventually, but this initial price hike is no doubt related to the Bulldozer launch.
    Reply
  • de5_Roy
    @compton: phenom might get a die shrink with the llano upgrade. according to the latest trinity leak, llano's new 'husky' core will feature a phenom ii class cpu with amd 6xxx class gpu. this is just a rumor though.
    Reply
  • soccerdocks
    Thank you very much for including Matlab in the benchmarks. Its a really informative benchmark for those in engineering.
    Reply
  • "Everyone was pulling for AMD to do something great with BD, and the efficiency results are just abysmal."

    Not really, for the most time everyone was aware that BD was not going to be a SB killer, AMD themselves had hinted at it, then their PR department (propaganda office I would say) started pumping up the hype.

    Reply
  • amk-aka-Phantom
    And this is exactly why AMD fanboys should STFU about Bulldozer being an "excellent server CPU". You don't want high power consumption on a server.
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  • amk-aka-Phantom
    dragonsqrrlYa, the MSRP is $332, but the price on newegg is $370. Even for a brand new processor that's a huge premium over MSRP. It'll stabilize to the $330 price range eventually, but this initial price hike is no doubt related to the Bulldozer launch.
    2700K is BS... 100MHz extra is definitely not worth it. 2600K and 2500K remain best bang for buck right now.
    Reply