The Phenom Inspired, Core i7-like, Phenom II

Want to hear something funny? When AMD launched the original Phenom, it was a unique looking architecture, something AMD touted as a significant advantage due to its "native" monolithic quad-core design (four cores, one die). I often argued that it wasn't an advantage, simply because the performance numbers didn't back up AMD's claims. AMD never won a real world desktop benchmark because of the monolithic quad-core design.

Intel followed up with Nehalem (Core i7), a microprocessor that had a very Phenom-like cache hierarchy (four cores, private L2 caches, one large shared L3 cache), but with much better performance.

Phenom II builds upon the same architecture as the original Phenom, hardly changed, but improves on a few key limitations. This isn't a new microarchitecture, this is a 45nm shrink of Phenom. In a sense, AMD gave up on improving the original Phenom. Early on after Phenom's release AMD went head in the sand and did whatever was necessary to make the 45nm transition perfect. Deneb, as it was called internally, had to succeed - because AMD as a company wasn't going to survive on the backs of the GPU division forever. It's somewhat ironic that Intel was able to execute a better Phenom-like microarchitecture before AMD.

Processor AMD Phenom II AMD Phenom Intel Core i7 Intel Core 2 Quad Q8xxx/Q9xxx
Manufacturing Process 45nm 65nm 45nm 45nm
L1 Cache 64K + 64K per core 64K + 64K per core 32KB + 32KB per core 32KB + 32KB per core
L2 Cache 512KB per core 512KB per core 256KB per core 2x3MB, 2x4MB or 2x6MB
L3 Cache 6MB 2MB 8MB -
Transistor Count 758M 450M 731M 456M (6MB/8MB L2) or 820M (12MB L2)
Die Size 258 mm2 285 mm2 263 mm2 164 mm2 (6MB/8MB L2) or 214 mm2 (12MB L2)

The above chart details the specifications for the current AMD and Intel quad-core offerings, and here we see a problem. Phenom II and Core i7 are around the same die size and have similar transistor counts, yet Core i7 sells for $284 - $999 while Phenom II sells for $235 - $275. The part that Phenom II actually competes with is the Core 2 Quad Q9400 (and perhaps the Q9550; more on that later), and that's a ~36% smaller die. This is the downside to AMD's pricing strategy; while it's great for consumers it's not particularly great for AMD's profit margins. The other thing to keep in mind is that at 214 mm2 Intel has an entire line of quad-core processors that, in theory, could be moved down the price list if the price wars of 2008 were to continue into 2009.

The move to 45nm was severely needed as you can see by the table above. AMD and Intel seem to agree on the right way to build a quad-core processor today: four cores with individual L2 caches (or one shared L2 per two cores on Intel) behind a large global L3 cache. Intel, however, waited until the 45nm transition was complete to move to that sort of an architecture in order to outfit the chip with a large enough L3 cache. AMD jumped the gun early with Phenom and was forced to limit its L3 cache size to 2MB on 65nm. Finally, with the move to 45nm, Phenom II boasts a 6MB L3.

The transistor counts of Phenom II and Core i7 are surprisingly close, as are the die sizes. The two chips are designed completely differently, but the end result is similarly sized processors. Note that both Phenom II and Core i7 are too big for high volume mainstream markets; the die size would need to be around half of what it is now to address those markets. AMD and Intel will do so by introducing dual (or triple in the case of AMD) core versions at 45nm and then transitioning almost exclusively to quad-core at 32nm.

Phenom II also marks AMD's return to the >$200 CPU market. The two parts launching today are the Phenom II X4 940 and the Phenom II X4 920, priced at $275 and $235 respectively.

Processor Clock Speed Uncore Clock L2 Cache L3 Cache TDP Price
AMD Phenom II X4 940 3.0GHz 1.8GHz 2MB 6MB 125W $275
AMD Phenom II X4 920 2.8GHz 1.8GHz 2MB 6MB 125W $235
AMD Phenom 9950 2.6GHz 2.0GHz 2MB 2MB 140W $174
Index Phenom II's Secret, In Pictures
Comments Locked

93 Comments

View All Comments

  • Walkeer - Thursday, October 15, 2009 - link

    Super, so because MS Vista has a really bad and stupid CPU scheduler, AMD had to disable perfectly legit and smart power saving feature = CnC per core rather than per chip. I really love windows! I expect that CnC per-core caused no problems under linux for example....
  • CuE0083 - Sunday, April 26, 2009 - link

    I have been a reader of this site for a few years (first time commenting) and I just wanted to know how you guys determine that a particular processor is a good overclocker.

    1) Do you guys try overclocking multiple chips?
    2) Do you just walk into the store, pick a random chip, and try overclocking it?
    3) Or does AMD send you a chip?
  • v12v12 - Thursday, July 23, 2009 - link

    All this bickering and nick picking—when to me the solution seems simple.

    All the poor folks clamoring about numbers they COULD NOT EVER POSSIBLY tell the difference if using Intel Vs AMD in a dboule-blind test! None of you can tell the measurable diffs in FPS and temp. It's all little programs with numbers telling you there's a difference. So wtf is all the fus about?

    Phenom-II is for people that already have an old AM2 rig and want to upgrade. But you forget that your old, slow ass mobo chipset and antiquated ram wouldn't even come close of a newer Intel system period.
    A Brand NEW Phenom-II would "compete," but it barely does that. And as prices drop Phenom-II is losing even more ground as someone with an intel 775 can spring for a fast Quad-core, while you're stuck with the SAME OLD MOBO and RAM DERRRRR?
    Stop all the nit-picking and bemoaning over Intel.

    Does it make sense to scrap your current AMD rig for a completely new Intel unit?

    YES = If you're doing video/AV editing and plan on getting an i7/i5 or if you’re not broke!

    NO = If you currently have an AMD and need some extra horse-power.

    But to falsely rationalize your purchase/mindset by suddenly putting the i7 into the "it's SO expensive" BS category; you're BROKE, you have no say about price. Get a real job and stop spending money on other nonsense and SAVE up like smart people do. It's YOUR own fault you cannot afford a damn $1100-1400 computer: that's NOT a lot. Just b/c YOU cannot afford it doesn't mean there's something "wrong" with i7.

    You're comparing a 2yr old Q6600 against AMD's newest unit LOL? That's like a car magazine comparing the newest lambo to a 2 year old Ferrari etc. BUT PRICE OMG... Prices steadily go DOWN, thus folks with 775 can still upgrade to 6700, 6800 and so forth.

    I'm glad AMD is "sort of" showing a rally to CATCH UP... BUT... when you buy into INTEL you're buying into a PROVEN ROADMAP OF PERFORMANCE VS AMD: you're buying into a mystery grab-bag of performance PROMISES.

    Geesh. Just get the Phenom-II if you cannot afford the i7. Nobody with sense is talking about going from a Q6600/9xxx to 2 year behind the pack Phenom. This is just sophomoric nonsense.

    Common-sense would tell you:

    1) GET A BETTER JOB (education/certs etc)

    2) Stop spending money on other hobbies and misc junk

    3) STFU already and improve your financial situation, THEN you have a say. It's YOUR fault you don't have enough for a paltry $1200 machine. WHO doesn't have $1200? If you don't you haven't EARNED the right to complain. Complain b/c it's someone else's fault - I'm betting it's mostly your own lack of saving & discipline that's the problem.

    None of you may like or agree w/me, but guess what? I don't care b/c I HAVE $1200 to spend so Fsck it I'm happy. Stop drinking, doing drugs, going out, blowing money on cable-TV and crap, for a change? Most of you are guilty of 1 or more of these frivolities.

    Honestly THINK about what you’re saying here? You’re complaining about a superior i7 that is too expensive to do WHAT— play some damn video games? So your rationale is to do what? Buy a new or CPU upgrade to do the same? So THUS instead of continually saving to get the best… You BLOW your loads for inferior technology… and so the cycle continues. You’re NOW BROKE AGAIN and behind. Maybe you’ll start saving once again and come out of the wood work 2-3yrs later and STILL be complain once again “OMG it’s TOO EXPENSIVE” “I’ll by the cheap crap instead!”

    LMFAO NOW THAT IS Ludicrous!
  • goofbud - Tuesday, December 6, 2011 - link

    Are you serious dude?

    It ain't the money. I know. I have money. I also have a lambo a porche and an evo. I like testing AMD because they give us "certified" techs something to tinker with and work on. AMD is a brand for builders and true techs like to tinker with a processor and see how far it can go. Even when I was in high school I owned 486's which were the latest and greatest that time. I had an INTEL PC and it sucked dirt once Microsoft came out with windows. Maybe Intel is ahead now but AMD is catching up. They can create the ultimate processor but they don't have to. Not yet.

    BTW, watch how you talk. Be considerate. It ain't the money man. I can afford to buy as many alienware pc's I want. But I don't. Am I a gamer? Yes! I have a powerful system now and am happy I did not spend a lot of money on it. See, this is the thing. If you are smart you just don't want to buy the fastest CPU and fastest RAM that comes out. It's like buying an PS3 for $6,000.00 on ebay just because you want to be the first to play it. That is stupid.

    People buy AMD because they are tweakable. They try to buy the cheapest parts out there, tweak it, and see how far it can go. Makes sense?

    So what if you have the fastest computer in the world. If you don't use it everyday you just wasted money.

    Understand now kid. Now STFU and Go to your room!
  • sandstones - Wednesday, March 25, 2009 - link

    I know that we should look at relative sysmark scores, but I'm still puzzled by the higher scores in this batch of tests, compared to those done in April 2008.

    For example the top performer from April - Core 2 Duo E8400 got a score of 161 on Overall in April 2008, and 191 in Jan 2009. The X4 Phenom 9750 went from 126 to 148. Other CPU's in both tests had similar differences. That's a bigger percentage difference than what gets used to debate whether Intel or AMD is better.

    Anand - any comments on what caused such a large difference?
  • Amitjakhar - Friday, February 20, 2009 - link

    http://www.overclockersclub.com/reviews/phenomii94...">http://www.overclockersclub.com/reviews/phenomii94...
    After overclocking it really comes near and sometime it gets better performance them Core i7. Which is good. AMD has done superb job and they are in the right direction. Next black edition will make Intel so worry they have to go to work again.
  • Amitjakhar - Friday, February 20, 2009 - link

    Phenom II is showing power much better then here. To me it seems they have not done the testing properly. You better check out this link and find how its performing genuinely
    http://www.guru3d.com/article/amd-phenom-ii-x4-920...">http://www.guru3d.com/article/amd-phenom-ii-x4-920...
  • salem80 - Tuesday, January 27, 2009 - link

    The Q9400 are 126W~174W not like what Intel said 95W ?
    even E8600 (124W~157W) while they say 65W ?
    their huge deferent in numbers here .
  • pcuser123 - Saturday, January 24, 2009 - link

    I think the new i7 core sucks compare Phenom II. Just look at the pricing vs performance on those two.
    Here is the benchmarks http://www.overclockersclub.com/reviews/phenomii94...">http://www.overclockersclub.com/reviews/phenomii94...
  • gipper - Monday, January 19, 2009 - link

    You do the overclocks but don't show us the results? Following overclocking, those stock processors have WIDELY different capabilities.

    I'd love to see those video encode charts redone with the overclocked processors. That would tell me the TRUE value of the 64x2BE, C2D, Phenom, PhenomII, and i7 relative to one another.

    Otherwise, your overclock information borders on worthless.

Log in

Don't have an account? Sign up now