If Bulldozer is the architecture that will compete with Nehalem, Bobcat is what will compete with Silverthorne. Bobcat is yet another ground up design from AMD, also due out in the 2009 timeframe, but it will address a more power constrained portion of the market. Systems that require a 1 - 10W TDP will use Bobcat, while Bulldozer is limited to the 10 - 100W range (obviously with some overlap between the two).

Bobcat is a far simpler core than Bulldozer, which allows AMD to place it in ultra low power devices (think TVs, set top boxes and smart phones), but it also means that costs will be low. Much like Intel's Silverthorne, Bobcat will be a part of a new class of extremely low priced x86 cores designed primarily for the consumer electronics market.

We asked AMD's CTO, Phil Hester, how simple of a core Bobcat would be - and the answer he gave us was quite telling. Two years ago Intel used the following chart to illustrate the need for multi-core CPUs, the driving factor being that you can no longer get good performance scaling by simply improving single core performance:

What isn't depicted on this chart is the relationship of power consumption to all of this, but as you can guess, the power consumption curve looks much like the multi-core curve. Incremental improvements in single core performance now require exponential increases in power consumption, which was a major driving factor behind the move to multi-core. By achieving higher performance through minor core improvements and adding more cores, we can maintain the sort of year-over-year performance increases we need while keeping power consumption in check.

Phil told us to imagine a graph of power consumption vs. instructions per clock over the history of microprocessor cores, which you can imagine would be linear for a while, before turning exponential.

We are presently in the very non-linear portion of the chart, where minor increases in IPC require significant power expenditures. Bobcat, takes the non-linear portion of this graph and chops it off, going back to a much simpler x86 core that can be built extremely efficiently on today's manufacturing processes.

If you can imagine a Pentium or Pentium Pro class microprocessor, built on a 65nm or 45nm process, you can already guess that power consumption would be quite low. Now add in a few optimizations that AMD's designers have learned over the years and you may be able to picture what Bobcat's architecture might look like. It harks back to a much simpler time in x86 history, but then again that's exactly what's necessary for the type of low power, low cost devices that Bobcat will end up in.

Bulldozer Performance Expectations Fusion


View All Comments

  • Lord Evermore - Sunday, July 29, 2007 - link

    What the heck are RDDR and UDDR? My only guess is the U might stand for the UMA design, but I don't know if that would be preferred for the server or workstation. Reply
  • Anand Lal Shimpi - Tuesday, July 31, 2007 - link

    RDDR = Registered DDR
    UDDR = Unbuffered DDR

    Take care,
  • Martimus - Thursday, August 02, 2007 - link

    Ok, what is OoO? I couldn't find it with a search on Google. Reply
  • Spartan Niner - Saturday, August 04, 2007 - link

    OoO is "out-of-order" referring to OoOE, "out-of-order-execution"">
  • Martimus - Monday, August 06, 2007 - link

    Thanks. Reply
  • xpose - Saturday, July 28, 2007 - link

    This is the best future roadmap article I have ever read. I am actually excited. No really. Reply
  • najames - Friday, July 27, 2007 - link

    I am an AMD fanboy, of 7 computers I have at home, only the 5 year old laptop has an Intel chip now. Dual cores are actually likely all I REALLY need. That said, I am sick of a bunch of hype and no new products. It's all blow and no show. I don't care about years down the road because it could all change between now and then.

    AMD/ATI could be a good thing too if they make good, polished drivers, 100% working for what was promised. How about throwing people a bone to make them switch, maybe even make some kick butt Linux drivers too.

    We were all on an AMD bus and nobody has been driving since the X2 chip. They taunted Intel and handed out huge bonuses, but forgot about any new development. I have to credit Intel, they kicked butt with Core 2, and seem to be doing more butt kicking going forward.

    I watched Hector on CNBC last night and he didn't look like he had a clue what was going on. Granted they weren't asking him details of any processors, but he was dodging basic business questions. Why do I have several hundred shares of AMD?
  • Regs - Monday, July 30, 2007 - link


    Why do I have several hundred shares of AMD?

    Because those relatively cheap shares, compared to Intel's, might be worth hundreds of times more one day from that stuff you call blow. Blow = prospects in business terms.

    I would say the same thing as you did though at first. It's obvious AMD and ATi's pipeline dried up and unfortunately both consecutively. You can argue that the 2900XT is a good card, performs well, etc..etc.. but that doesn't explain why AMD offers crapware for main stream (where the real money is). As for AMD's CPU line can only sell old for so long in the technology sector without taking a hit.
  • kilkennycat - Friday, July 27, 2007 - link

    .... dump ATi. The marriage made in hell. New products unable to meet schedule and with inferior performance, thus no way of rapidly recovering development costs by pricing for performance.

    Dave Orton sure did a neat sell-job on AMD, walking away with $$millions when AMD paid a 20% premium for a chronically non-performing company barely managing to eke out some tiny profits during the last couple of years. No wonder Mr. Orton was finally shown the door.
  • kleinwl - Friday, July 27, 2007 - link

    What is the problem with AMD, did they not receive enough feedback that UVD is a "must have" on high end units. I don't want to have choose between good gaming performance and movie performance... I am paying a ridiculous premium already for hardware... the least they could do is make sure it has all the bells and whistles. Reply

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