AMD Phenom II X6 1090T

Socket Type: AM3
Number of Cores: Six
Operating Frequency: 3.2GHz
Front-Side Bus: HyperTransport 3.0
Cache Memory: 9MB (combined L2 and L3)

AMD’s first pair of six-core CPUs, the $285 Phenom II X6 1090T that we’re looking at here, as well as the $200 Phenom II X6 1055T (announced on the same day), aren’t exactly cheap. But compared with Intel’s sole six-core CPU (as of this writing), the $1,000 Core i7-980X, which launched last month, AMD’s offerings are downright thrifty. Indeed, while AMD’s new chips have names only a tax accountant could love, you probably won’t have to blow much of your federal return on one of these six-core wonders. That’s more than we can say about Intel’s six-core offering.

At their under-$300 prices, it’s no surprise that AMD’s six-core chips don’t run as fast as Intel’s top-end CPU speed demon. But with features like dynamic CPU clock speeds and compatibility with existing AM3 systems, they further cement AMD’s dominance in terms of both upgrade flexibility and performance for your dollar. Intel still holds a strong lead in ultimate performance, but in our tests, the Phenom II X6 1090T performed right in line with Intel chips that currently sell for nearly twice as much.

First though, let’s discuss who can actually make best use of high-end CPUs like these. As much as both Intel and AMD may lament it, most software still can’t take advantage of more than one CPU core at a time. For most everyday computing situations, unless you’re somehow tackling six CPU-intensive tasks at the same time, your six cores won’t make anything happen any faster. Even four cores is overkill for many users, which is why we continue to tout options like AMD’s $100 dual-core Phenom II X2 555 and triple-core $75 Athlon II X3 435 as good options for budget gamers, or those who just want a speedy, inexpensive CPU for average computing tasks.

To get around the limitations of current software, AMD has added dynamic core clock speeds to this processor, employing a technology it calls Turbo CORE. With Turbo CORE, the base clock speed (3.2GHz, in the case of the Phenom II X6 1090T) will ramp up to as much as 3.6GHz automatically when the CPU is churning away on a task that can only make use of a single CPU core. Intel’s version of this technology, which it calls Turbo Boost, has been available on higher-end Intel CPUs since mid-2009. This feature is a welcome addition to any CPU, to be sure. But unless you rely on software that actually uses all available cores, you won't see the full benefit of paying for those additional cores. Most such software comes from the professional content-creation realm. For those who rely on programs like Adobe’s Creative Suite or Sony’s Vegas video editor (or similar programs that are expressly multi-core aware), stepping up to a six-core processor can mean a serious speed-up, especially if they are currently running an aging dual-core CPU.

On the other hand, gamers (at least today) won't be the primary beneficiaries of six-core tech—except under certain circumstances. A few titles do take advantage of multiple cores. (In those games, the extra cores allow the game to handle more-complex artificial intelligence for non-player characters.) But again, while a handful of games qualify, and more are on the way, most games currently on the market won't see a significant benefit from six cores, especially if you're already running a fast quad-core CPU.

So, if you find yourself in one of those two camps (or straddling the two), six-core CPUs can be a smart choice. Those editing massive amounts of HD video on a tight schedule may wish to pay the premium for Intel’s faster Core i7-980X CPU, but there’s no denying that AMD’s Phenom II X6 1090T is plenty speedy. And what makes its under-$300 price extra-appealing is that you can drop the chip into an existing AM3 or AM2+ motherboard, making the entry cost for hexa-core computing that much cheaper if your PC is ready to accept the chip. (A BIOS update will be necessary, though, so be sure one is available for your board before buying.)

To see how the Phenom II X6 1090T stacks up against similar CPUs, we ran it through our spate of tests designed to measure general performance, as well how it handles tasks that fully tax its six cores. First up, in PCMark Vantage, a synthetic test designed to measure overall system performance, the Phenom II X6 1090T managed a score of 7,462 in our test rig. That puts it ahead of the 6,583 turned in by Intel’s quad-core (and currently $550) Core i7-870. Intel’s current six-core king, the $1,000 Core i7-980X, slid in well ahead, with a showing of 9,822.

We then moved on to Cinebench 10, another CPU-centric test designed to tax multiple processor cores. The Phenom II X6 1090T again ran a bit ahead of the Core i7-870, with a score of 17,812 to the Core i7-870’s 17,542. But the Core i7-980X’s showing of 26,981 puts Intel's six-core chip in another league (which is, truth be told, where it belongs for the price).

We then moved to our iTunes conversion test, which can only make use of a single CPU core. (In the test, iTunes converts 11 standard MP3 files to AAC format.) This test shows the limitations of six-core CPUs—AMD’s and Intel’s alike—in most everyday tasks. The Phenom II X6 1090T actually came in third here, converting our 11 test files in 2 minutes and 48 seconds. The quad-core Core i7-870 came in six seconds faster, while the six-core Core i7-980X again came out on top, finishing in just 2:26. The fact that these scores were much closer demonstrates how users who don’t rely on software that can tax extra cores won’t notice much real-world difference among any of these three high-end CPUs.

In video editing with Sony’s Vegas Pro 8 however, multiple cores make much more of a difference. In our Vegas 8 MPEG-2 render test, the Phenom II X6 1090T encoded our test file in 2 minutes and 23 seconds, while the Core i7-870 did surprisingly well with its four cores, finishing just 3 seconds behind. But the Core i7-980X showed its true dominance here, finishing in just 1:40. For those encoding very large files, those time differences will be of even greater significance. The takeaway: The Core i7-980X is much faster in this regard—if you can afford it—but considering that the $285 Phenom II X6 1090T does about as well as the (currently) $500-plus Core i7-870, video editors and content creators who don’t need the absolute fastest speeds should take a long, thoughtful look at this AMD chip.

Those upgrading or building a new PC should also consider the simplicity and relative affordability of AMD’s hardware platform as a whole. The new 890GX chipset supports all current-generation AMD CPUs and dual-channel DDR3 memory. Comparatively, the complexities of Intel’s current CPU lineup, which employs two different CPU sockets (LGA 1156 and 1366) that support, respectively, dual- or triple-channel DDR3 memory, seem downright confusing. On the practical side, the fact that AMD has stuck by a single socket standard means that current AMD motherboards have much more upgrade flexibility than recent Intel ones. With the Intel boards, you’ll have one of the two aforementioned socket types, and be locked into that particular socket’s cost and performance limitations until you’re ready to buy a new motherboard.

In terms of performance, though, little has really changed. As has been the case since the launch of the initial Intel Core i7 CPUs in November of 2008, Intel holds a strong lead over its CPU rival AMD at the very high end of the consumer-CPU market. But down in the realm of affordable chips, AMD has been doing quite well for itself with impressive offerings like the $120 quad-core Athlon II X4 635, which is, in most tests, a fair bit faster than Intel’s similarly priced, dual-core Core i3-530.

And in the world of six-core CPUs, things are decidedly similar today. To summarize: In our battery of tests, AMD’s new six-core flagship chip, the Phenom II X6 1090T, is a very strong performer in the $300 price range. Unsurprisingly, it doesn’t match the performance of Intel’s $1,000-plus, six-core Core i7-980X, or even the quad-core Core i7-975, which sold for about $970 when we wrote this in late April 2010. But it ran pretty close to even in our tests with Intel’s quad-core Core i7-870, which sold for $550.