Intel Core i5-661: Clarkdale Rings The Death Knell Of Core 2


So as we draw our entry-level epic to a close, it’s time to reflect on what we’ve just seen and—almost as important—what we haven’t seen yet. Intel sent one processor over to represent the Clarkdale lineup: the Core i5-661. Up near the top of the Clarkdale stack, i5-661 gives us the quickest graphics core, clocked at 900 MHz. It runs at 3.33 GHz and Turbos up to 3.6 GHz.

But it also costs $200. Lots of stuff costs $200. In fact, every one of the processors in our test lineup approaches the $200 mark—and there were some definite favorites. In the threaded applications, Intel’s Core i5-750 was perhaps the strongest contender. Don’t forget AMD’s Phenom II X4 965 Black Edition—another powerful option.

Intel admits that its Core i5-661 will probably be a relatively low-volume part for SIs who prefer integrated graphics as a means to minimize total system power consumption. The merits of this approach are reflected in an efficiency story from Patrick going live tomorrow, where we see integration playing a huge role in improving the performance per watt of power used. The company expects Lynnfield to continue serving as its volume driver in the enthusiast space. But with that said, we've seen some early numbers from Intel with the Core i3-530, and the results aren't really that far off of the Core i5-661 in threaded applications, once you take away the benefit Turbo Boost gives to the higher-priced model.

Is there any reason to buy Core 2 Duo or Core 2 Quad processors now that Clarkdale is here, front and center? Core 2 Quad: sure—it still shows fairly well, and might make a reasonable upgrade if you don’t want to replace your LGA 775 motherboard. Core 2 Duo: no, not really. Though the Core i5-661 is also a dual-core CPU, its use of Hyper-Threading and Turbo Boost makes it superior in both parallelized and single-threaded applications. The Core 2 Duo E8500 did win a couple of tests against Clarkdale, but when it lost, it lost big.

Unfortunately, Intel did not send any of its lower-cost models, which would have invariably had to stand up against lower-clocked quad-core contenders from AMD. No worries there. Once the CPUs are available at retail, you can be sure we’ll grab a couple and run some tests of our own to see how Clarkdale-based Core i3s do battle once you take away Turbo Boost.

Until then, we’re left with a positive impression of Clarkdale as the engine in a business platform, specifically. The Core i5-661 we tested—which could easily be substituted for the i5-660 at the same price point—completely eclipses the Core 2 Duo E8500 and solidly rivals some of the fastest Core 2 Quads. Our opinion is reinforced by Intel’s limiting the H55 and H57 chipsets to a single graphics card. Moreover, the company’s simultaneous launch of the Q57 platform gives the channel AMT 6.0 for out-of-band management. Business, business, business.

Clarkdale also shows promise in the home theater. Support for hardware accelerated Blu-ray playback, multi-channel LPCM output, and lossless bitstreaming of high-def audio formats leaves very little else to be desired from a media-oriented platform, so long as you don’t intend to game on it. Not having to buy a discrete Radeon HD 5000-series graphics card means we’ll be seeing remarkably powerful mini-ITX platforms with 73W Clarkdale CPUs taking care of processing and graphics in one compact (affordable) package.

What about the enthusiast? At least at the upper range of the mainstream segment, Core i5-750 and Phenom II X4 965 rule the roost. P55 is still going to be your platform of choice, too.  But does that mean we’re counting out a Clarkdale/P55 combination? Not at all. Once the motherboard vendors start releasing BIOS updates that solidify Clarkdale support on P55 platforms with discrete graphics, we’ll revisit the matchup with a mind to overclocking. We’re curious to see if brute-force overclocking will allow the 32nm Hyper-Threaded Core i5 to overcome the i5-750’s four cores. After all, 4.5 GHz on air isn’t half-bad.

Chris Angelini
Chris Angelini is an Editor Emeritus at Tom's Hardware US. He edits hardware reviews and covers high-profile CPU and GPU launches.
  • Zoonie
    Well... I think that takes care of the dreaded "But can it play Crysis?" question regarding its GMA :D :P :P
  • xc0mmiex
    Video on page 1 not working ... "This is a private video..."
  • eklipz330
    can i ask why you teased us at the end with the 4.5ghz OC but didn't include them in the benchmarks? =
  • cangelini
    xc0mmiexVideo on page 1 not working ... "This is a private video..."
    Fixed! Had to keep it private pre-launch :)
  • I really like the improvements Larrabee brought about....not! I do like the fact they are making progress but they really need to skip ahead a few generations or buy out some other company to design a GPU for themselves.
  • gkay09
    ^ Many more reasons to buy AMD Phenoms II X4 in the mid-range segment...
    Only drawback with the AMD CPUs is the power consumption, that I feel can be brought down with slight undervolting...
  • dtemple
    I'm looking to upgrade from my Athlon X2 @ 2.7GHz because I do more with the computer now than I did before - sometimes I'll play a game while my TV tuner is recording from my cable signal, and having more cores would help these multiple tasks run more smoothly.
    I was waiting until the Clarkdale-based i5 launched, thinking it would be a quad-core that was more competitively priced against the Phenom II X4, but it looks like a Phenom II X4 is my only option to get more cores for less money.
    The only good news coming out of this launch is that LGA1156 is not changing for the Clarkdale chips, so it looks to be the most future-proof platform to upgrade to, if one was so inclined. I'm personally going with a Phenom II since I can get one without changing motherboards. This is one of the more disappointing launches in the last year or so.
  • cangelini
    eklipz330can i ask why you teased us at the end with the 4.5ghz OC but didn't include them in the benchmarks? =
    We have another overclocking piece planned--I wanted to get a Core i3, at least, to include :)
  • I would love to see what GTA IV would do do the dual cores in gaming! I do know that its a bear of a game on the CPU and it would truly show off if hyperthreading could actually make a major difference.
  • maximus20895
    Great video once again! Thanks for this and the review itself. Very informative. I really liked the graph on the first page too :)