Intel Core i7-875K And Core i5-655K Battle Beyond 4 GHz


Drawing conclusions on this one is surprisingly easy. Intel gets major kudos for going somewhere it has never gone before: opening up enthusiast-class flexibility to the folks who don’t have $1,000 to spend on a new CPU.

It wouldn’t be fair to sarcastically toss out a, “way to join the party, Intel.” Remember that once upon a time, AMD only unlocked its $1,000 FX-series chips, too. But getting eclipsed on the performance front encourages creative thinking. The fact that Black Edition CPUs are available under $100 is less altruistic and more strategic.

At the end of the day, it’s all good news for enthusiasts, who now have more choice and more flexibility at price points they can more realistically afford.

…versus Intel

If you’re looking at Intel’s product stack, these new chips (particularly the Core i7-875K) are just what the doctor ordered. I mean, I wouldn’t have ever suggested that a 2.93 GHz Core i7-870 was a good buy at $562 when the 2.8 GHz Core i7-920 was selling for $294. But a Core i7-875K at $342 is at least a little more attractive if you’re using that $562 price point as a reference.

At the same time, an unlocked Core i5-655K at $216 doesn’t sound daunting at all. For a processor that ran stable for us at 4.66 GHz, you couldn’t really ask for sweeter dual-core chip to take the place of Intel’s Core 2 Duo E8500 and E6300 in the annals of overclocking history.

At the same time, we have to wonder why Intel picked the SKUs that it did for K-series honors. Tom’s Hardware’s favorite overclockable Core i7 remains the LGA 1366-based -920 (or -930). Our favorite i5 remains the -750. Either one of those models, unlocked, could have been priced similarly, opening up X58’s PCI Express connectivity at the high-end, and giving enthusiasts a true quad-core LGA 1156 CPU with which to play, even if it’s a more-expensive-to-manufacture 45 nm design.

…versus AMD

And that leads to the inevitable comparison to AMD’s Black Editions.

Versus the Core i7-875K, overclocked, AMD’s six-core Phenom II X6 1090T is generally outperformed at 4 GHz. But it’s also $30 cheaper. It also takes off in heavily-threaded video encoding titles. And it also populates a platform well-endowed with PCI Express 2.0.

While you could easily set the Core i5-655K up against AMD’s Phenom II X6 1055T, we chose the quad-core Phenom II X4 965 instead, which also hit 4 GHz stably. Threaded titles uniformly favored AMD’s offering, while workloads like iTunes gave the 32 nm chip’s insane 4.66 GHz clock the advantage. Again, though, Intel is asking an extra $35 over AMD’s price of entry.

Bottom Line

As enthusiasts, we’ll again emphasize how happy we are to see Intel unlocking processors beyond its Extreme Edition parts.

But despite the excellent scaling you get from the company’s more advanced manufacturing technology, AMD’s Black Edition parts still come across as better values for the money, even when you overclock both parties involved to the limits of stability. With a slight massage to each model's price point, though, this story could easily turn back around and go the other direction.

The K-series chips give Intel significantly more street cred. Here's hoping the product family lives on and expands to include additional enthusiast-class parts.

Follow Chris Angelini on Twitter for updates from the Tom's Hardware lab.

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Chris Angelini is an Editor Emeritus at Tom's Hardware US. He edits hardware reviews and covers high-profile CPU and GPU launches.
  • xurwin
    BE vs K!! go K series
  • sarsoft
    LGA 1366 i7 hopefully will be available soon. GRRRRRRRRR........
  • Known2Bone
    wow now that is some serious over-clocking... and here i am trying to push my 955 up past 3.93. i would have liked to see some liquid cooling tossed in to spice things up and maybe one more 5970... great job Chris!
  • cangelini
    Known--I'll talk to Thomas about getting some of that going in his next System Builder Marathon piece. He loves liquid cooling =)
  • hok
    still love my 930...
  • Stardude82
    Intel did release the E6500K for the LGA 775, but only in Asia.

    The only good thing here is that these chips will probably ship with heat sinks that don't suck and a good price drop for the i7 870. Otherwise, who cares, FSB stability on decent P55 boards has not been a problem. What the socket really needs from Intel is a better chip-set, not easier overclockers.
  • nurgletheunclean
    9. All prize winners are responsible for taxes and other surcharges on the prizes they win.

    1099'd for $1499? I hate how contest prizes all have full MSRP on everything. Even if you win it end up costing you $500+ in taxes.
  • SpadeM
    Intel makes good cpus, that's a given. Their problem lies in the pricing of such chips. I mean if you could buy a processor because you want to overclock it then the locked but cheaper one is as good as the unlocked one. Sure, it's more difficult, but I for one love a challenge.

    Also, as a side note, I do have a problem with the benchmarks and more accurately with the conclusion you extracted from them. Who in their right mind would buy a processor, overclock it, and then do iTunes all day ... I mean come on, there's more to life then music ripping. What I'm saying is that the benchmark section SHOULD be remade entirely. Same old tests, that I could anticipate the outcome of every time, isn't a very compelling way to make a point. I do appreciate the game section though, at least i saw a new title.
  • jecastej
    Finally, very good news for serious desktop processing power that wont leave me with an empty wallet. The 875K is going to be my next CPU for 3D modeling and rendering. I hope it will keep me entertained for a while =)

    Don't get me wrong but I was getting bored with the tiny world of ARM and Tegra and on the other side of the spectrum the hexacores and dual Xeons were far and away for my budget.
  • anamaniac
    sarsoftLGA 1366 i7 hopefully will be available soon. GRRRRRRRRR........On, I just read about a guy reaching 4.644GHz on air with his i7 930. Granted, he has a great chip, but by no means is a unlocked multiplier needed for high overclocks.

    If I were to build a new PC, the 1090T/1055T would be very complelling.