This is a very volatile time for Intel. In an ARM-less vacuum, Intel’s Haswell architecture would likely be the most amazing thing to happen to the tech industry in years. In mobile Haswell is slated to bring about the single largest improvement in battery life in Intel history. In graphics, Haswell completely redefines the expectations for processor graphics. There are even some versions that come with an on-package 128MB L4 cache. And on the desktop, Haswell is the epitome of polish and evolution of the Core microprocessor architecture. Everything is better, faster and more efficient.

There’s very little to complain about with Haswell. Sure, the days of insane overclocks without touching voltage knobs are long gone. With any mobile-first, power optimized architecture, any excess frequency at default voltages is viewed as wasted power. So Haswell won’t overclock any better than Ivy Bridge, at least without exotic cooling.

You could also complain that, for a tock, the CPU performance gains aren’t large enough. Intel promised 5 - 15% gains over Ivy Bridge at the same frequencies, and most of my tests agree with that. It’s still forward progress, without substantial increases in power consumption, but it’s not revolutionary. We compare the rest of the industry to Intel’s excellent single threaded performance and generally come away disappointed. The downside to being on the top is that virtually all improvements appear incremental.

The fact of the matter is that the most exciting implementations of Haswell exist outside of the desktop parts. Big gains in battery life, power consumption and even a broadening of the types of form factors the Core family of processors will fit into all apply elsewhere. Over the coming weeks and months we’ll be seeing lots of that, but today, at least in this article, the focus is on the desktop.

Haswell CPU Architecture Recap

Haswell is Intel’s second 22nm microprocessor architecture, a tock in Intel’s nomenclature. I went through a deep dive on Haswell’s Architecture late last year after IDF, but I’ll offer a brief summary here.

At the front end of the pipeline, Haswell improved branch prediction. It’s the execution engine where Intel spent most of its time however. Intel significantly increased the sizes of buffers and datastructures within the CPU core. The out-of-order window grew, to feed an even more parallel set of execution resources.

Intel added two new execution ports (8 vs 6), a first since the introduction of the Core microarchitecture back in 2006.

On the ISA side, Intel added support for AVX2, which includes an FMA operation that considerably increases FP throughput of the machine. With a doubling of peak FP throughput, Intel doubled L1 cache bandwidth to feed the beast. Intel also added support for transactional memory instructions (TSX) on some Haswell SKUs.

The L3 cache is now back on its own power/frequency plane, although most of the time it seems to run in lockstep with the CPU cores. There appears to be a 2 - 3 cycle access penalty as a result of decoupling the L3 cache.

Power Improvements
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  • Nacho - Saturday, June 1, 2013 - link

    Maybe it's time to upgrade my C2D E4300? :P
  • krumme - Saturday, June 1, 2013 - link

    Absolutely, go get a good ssd and this processor or IB, if its for desktop.
  • Oscarcharliezulu - Monday, June 3, 2013 - link

    Do it.
  • Boissez - Saturday, June 1, 2013 - link

    So my 2½ year old 2600K ($317) performs about the same as todays 4560K ($242). Color me underwhelmed.

    Meanwhile in mobileland we've went from 1 Ghz Tegra 2 to 2 Ghz Snapdragon S600 within the same timespan.
  • tential - Saturday, June 1, 2013 - link

    Because for 99.9% of the population what's out there today is more than fast enough. Hell, the Core2Duo Conroe/Penryn processors are fast enough for most people today. I'm still using one in fact.

    On the mobile side however, we have tons of applications that could use more power. My galaxy S3 takes a little to load up some games, and while the data may have been downloaded to the phone through wifi, it still isn't on my screen yet.

    I think it's pretty obvious why you see mobile land having to progress so fast while desktop processors are focusing on power consumption as the AVERAGE consumer (not people who are techies) would prefer smaller PCs and pushing more power efficient processors into smaller and smaller things like the intel NUC is what the consumer desires.

    In short:
    Your desires are the 1%. The 99% are being catered to.
  • klmccaughey - Monday, June 3, 2013 - link

    @tential: Your last statement, maybe it should read "OUR desires are the 1%"? ;) I bet we would all be clapping right now if the 4770k was a big upgrade. Well, most of us, I think?
  • jeffkibuule - Saturday, June 1, 2013 - link

    Mobile is having the same performance renaissance that desktop chips had from 2004-2006 when we went from a hot, bloated Pentium 4 to a cool, efficient Core 2 Duo. And certainly we've had performance gains since then, but eventually the gains won't come so easily. You can start to see that a bit now with how the Exynos 5250 in the Nexus 10 is thermally throttled to 4W such that CPU and GPU can't be both running full tilt at the same time.
  • Homeles - Saturday, June 1, 2013 - link

    You're disappointed because your understanding of physics and Moore's Law is poorly developed. The scenario you've provided is a blatant false equivalency.

    According to your desperate desires, the roughly 4GHz processors that launched with Sandy Bridge should be running at twice the clock speed today.

    When you understand that leakage power grows exponentially as transistor geometries shrink, and that power consumption raises exponentially as clock speed rises, you will realize that even the 10% gains that Haswell makes here are a big deal.
  • Dal Makhani - Saturday, June 1, 2013 - link

    Homeles, I really appreciate your well said comment, im taking a business degree with an accounting major, but ive always loved building PC's as a hobby. When some of my computer science/engineer friends try to show me the stuff they are learning, i am baffled as its not my area of expertise. I can only imagine how challenging it is to combat the shrinking processes and make performance gains as you said. I have deep respect for Intel and AMD, always trying to utilize their research and engineers to try and make any gains for society. These forum people are just so ignorant sometimes and it baffles me.
  • chizow - Saturday, June 1, 2013 - link

    Hey, similar path as me. :) Don't worry about lack of understanding now, stick to it, keep reading great technical sites like AT, keep an open mind, and you'll get a really good grip on the industry, especially if you are an actual user/enthusiast of the products.

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