AMD FX-8150 Review: From Bulldozer To Zambezi To FX

Perhaps the most hotly-anticipated launch in 2011, AMD’s FX processor line-up is finally ready for prime time. Does the company’s new Bulldozer architecture have what it takes to face Intel’s Sandy Bridge and usher in a new era of competition?

How much CPU do you really need? Two cores? Four? Six? In many ways, the answer depends on what you’re doing with your PC. We’ve found that most games run best on machines with at least three cores. We know that many video editing apps use as much processing horsepower as you give them. And many productivity-oriented titles don’t take advantage of parallelism at all.

Really, the key to a healthy machine is balance. Balance prevents bottlenecks. We’re long-time proponents of balance (see Paul Henningsen’s Building A Balanced Gaming PC series). And now, as a purveyor of processors and graphics, AMD stands to profit handsomely from preaching the very same message.

But when the marketing slides detailing a company’s upcoming flagship desktop processor demonstrate a trend favouring cheaper PCs, you have to expect a CPU designed for cheaper PCs. I hope this isn’t too much of a spoiler, but enthusiasts who were hoping to see AMD’s Bulldozer architecture decimate Sandy Bridge and do battle with Sandy Bridge-E have to adjust their expectations. Instead, the company is going after a burgeoning chunk of the market looking to spend less on hardware than they did in the past.

That’s cool though, right? Sandy Bridge showed the power user community that they didn’t need a $1000 processor to get blazing-fast performance. An unlocked $200 chip capable of reliably hitting 4.5 GHz smoked Intel’s Gulftown-based Extreme Edition parts in a number of desktop-oriented tests (including the ever-important gaming scenarios). If AMD can offer a better value in that market, you won’t hear me (or anyone else) complain.

Meet The FX Family

At least on paper, the line-up of processors AMD plans to roll out looks both comprehensive and competitive. There are seven models in the FX family, ranging from the FX-8150 down to the FX-4100. They all centre on AMD’s Zambezi design, manufactured on Globalfoundries’ 32 nm node and composed of roughly two billion transistors. The 315 mm² die is smaller than Thuban (at 346 mm²), but larger than Deneb (at 258 mm²). Sandy Bridge, in comparison measures 216 mm².

The portfolio is most easily broken down into eight-core, six-core, and four-core CPUs (corresponding to four, three, and two Bulldozer modules). Model numbers do help you identify the chips somewhat: an FX-8xxx is an eight-core SKU, for instance; FX-4xxx is a four-core product.

The three digits that follow the core designator arbitrarily indicate performance within the stack. They aren’t consistent with clock rate, TDP, or L2 cache. You simply have to remember that, within the FX-8xxx segment, -8150 is better than -8120, which is better than -8100.

All of the FX processors are multiplier unlocked up and down the line-up, so there may turn out to be some interesting bargains, depending on how aggressively AMD is speed-binning these CPUs. Remember back to 2008, when Intel launched Nehalem? Enthusiasts jumped all over the 4 GHz-capable Core i7-920 because it was cheap. It remains to be seen whether Globalfoundries’ 32 nm process can achieve the same notoriety.

AMD makes it super-easy to avoid naming confusion at launch by making four CPUs available: the FX-8150, the -8120, the -6100, and the -4100.

That quartet of FXes picks up from where the Phenom II family left off, price-wise. AMD's FX-4100 overlaps the prior generation with a $115 price tag, serving up four cores and clocks between 3.6 and 3.8 GHz (max. Turbo Core). FX-6100, running at a base 3.3 GHz and maxing out at 3.9 GHz, sells for $165. The -8120, armed with eight cores, a 3.1 GHz base, and 4 GHz peak Turbo Core clock, is expected to go for $205. And the flagship -8150, which pushes frequency up to 3.6 GHz base and 4.2 GHz maximum Turbo Core, bears a $245 suggested retail price.

AMD only sent one of the four models for evaluation: the -8150. Our impressions on the other three processors will have to wait, unfortunately (that’s a hint, System Builder Marathon team). We don’t have any additional details as to when the other three FX processors will hit the channel, or how much they’ll cost. But we're finding it hard to care right now. We have the fastest model sitting on our test bench and a list of updated apps with which to test, based on your feedback. So, let's get to it.

*UK pricing not yet available.