AMD Phenom II X6 1090T: Six Cores on a Shoestring Budget

With the release of Intel's six-core Core i7-980X Extreme Edition processor, it was only a matter of time before AMD launched their retort: the six core Phenom II X6 1090T.

At a glance, it's apparent that the 3.2GHz Phenom II X6 1090T lags behind Intel's six-core behemoth. Previously codenamed Thuban, the 1090T is a 45nm part, while Intel's 980X has been shrunk down to the 32nm process. Where the 980X offers a 12MB L3 cache for improved memory management between multithreaded applications, the 1090T offers only 6MB. And AMD's technology doesn't address Intel's much touted Hyper Threading technology, which turns their six-core processor into twelve available cores for applications to dabble with.

By most measures, Intel's six-core processor is the superior part. But in typical AMD fashion, what the Phenom II X6 1090T lacks in raw power, it makes up for with a tantalizingly competitive price: the 1090T can be had for as little as $300. By comparison, Intel's admittedly superior silicon comes with a $1000 price tag, making it virtually inaccessible for many enthusiasts. And that's assuming you already have a compatible motherboard. The 1090T offers drop-in support with existing AM3 and AM2+ socket motherboards, after a BIOS upgrade. The 980X, by contrast, requires the LGA 1366 socket.

We just have to wonder: is that $700 difference worth it?

A Tale of Two Chipsets

The launch of the new Phenom II X6 platform is linked to the launch of the new 890FX chipset. We tested the 1090T on one of the first boards to support the new chipset, an Asus Republic of Gamers Crosshair IV Formula motherboard. The 890FX chipset bears much in common with the 890GX chipset we reviewed in March, and features support for SATA 6GBp/s, delivering transfer speeds of about 500MB/s. While the 890FX chipset lacks integrated graphics, it nearly doubles the number of available PCI lanes -- 42, against the 890GX's 22.

A greater number of lanes per slot translate into greater available bandwidth for installed hardware. As AMD's handy diagram explains (click for greater detail), the 870FX chipset offers support for up to two PCI Express 2.0 x16 slots, which operate as four x8 slots, if you add four graphics cards. By contrast, the 890GX's pair of x16 slots operate as a pair of x8 slots if you add two graphics cards. The 870FX chipset also offers six x1 slots and one x4 Express slot, as well as another pair of x1 slots located on the SB850 southbridge. Like the 890GX, the 890FX chipset lacks native USB 3.0 support -- the Crosshair IV offers USB 3.0 care of an NEC host controller.

Performance, When You Need It

One of the Phenom II X6 platform's oft-touted features is its Turbo Core technology, AMD's answer to Intel's Turbo Boost. The premise behind both Turbo Core and Turbo Boost is that many applications often aren't making full use of multicore processors. Unused cores translate into unused processing potential. The solution: automated overclocking.

In Intel's case, when the processor's cores are operating below heat and power limits, the clock frequency of any active cores will automatically increase. If a single core is active and five are idle, the active core will see its clock speed bumped up. If all six cores are active but not operating at maximum capacity, they'll still see a boost, while remaining within the specified thresholds. AMD's Turbo Core functions similarly. When up to three cores are being underutilized, the active cores will see their frequencies boosted by up to 500MHz. With Turbo Core enabled, the 3.2GHz 1090T we reviewed can reach up to 3.6GHz.

Our Testbed

For our tests, we coupled the Crosshair IV motherboard and the 1090T processor with 4GB of DDR3-1333MHz RAM, an ATI Radeon HD5870 graphics card, and a 1TB hard drive. We ran all of our tests on Windows 7 Ultimate Edition (64 bit). It's worth noting that our testbeds for both the Core i7-980X and the 1090T were nearly identical. The chief differences were the divergent chipsets, and the amount of RAM included. Intel's Core i7-980X and X58 chipset offer support for triple-channel memory, and were thus saddled with 6GB of DDR3-1333MHz RAM.

Six Cores for Play

Intel positioned its Core i7-980X as the premier part for enthusiast gamers, and the part performed amicably. And as expected, AMD's part lagged behind -- at times. For our first test, we tackled Massive Entertainment's World in Conflict, a DirectX 10 real time strategy game. At a resolution of 1920-by-1200 pixels (highest settings, AA and AF disabled) we saw 79 frames per second out of the 980X.

The 1090T, by comparison, managed 55 frames per second. While both are certainly playable framerates, the 980X boasts a staggering 43.6% increase over the 1090T. For comparison's sake, with Turbo Core disabled the 1090T offers up 50 frames per second. At first blush, it would seem that despite the minor boost from Turbo Core functionality, AMD's six-core technology simply can't compete.

Things start to look a little differently once we take a look at Codemasters' Dirt 2 -- a DirectX 11 title. With Turbo Core enabled, we saw 76.5 frames per second (1920 by 1200 resolution). The 980X offered 73.3. While a 4.1% difference in favor of AMD is meager, it's still an improvement. For curiosity's sake, disabling Turbo Core on the 1090T pulls the frame rate down to a still respectable 70.6.

Six Cores For Work

Games are always fun, but the deciding factor for many users will be how the 1090T holds up against Intel's 980X when play time is over. As expected, the 980X was the clear victor across the board. That being said, AMD's 1090T put up a strong fight. Our Photoshop test pits our testbeds against an array of high resolution images, challenging them to churn through a series of editing tasks. The 980X was 31.7% faster than the 1090T. Media encoding fared a bit better: the 980X was 15.3% faster at our Roxio VideoWave editing task, and only 5.52% percent faster at encoding a test film clip using Windows Media Encoder.

Power Consumption

While AMD has historically been the power-conscious alternative, things are a bit different at the six-core level. The 1090T is a 125W TDP processor, similar to the quad-core part it succeeds. But while the 980X reports a TDP of 135W, it's been shrunk down to the 32nm process, which offers tangible power savings. When idle, our 1090T testbed drew 85.2 watts of power, as compared to the 980X's 95.3 watts. At peak levels, the roles were reversed: the 1090T drew 230 watts, as compared to the 980X's 210 watts. For comparison, Intel's quad-core 45nm Core i7-975 Extreme Edition processor drew 231 watts.

The Final Verdict

The Core i7-980X is the clear performance winner, boasting improved performance while even offering 12.1% less power consumption. But let's be honest here: $1000 for a single component shoves it well out of the realm of most, to say nothing of additional upgrade costs should your sockets fail to match. And while price generally isn't a factor in our reviews, we'd be hard pressed to skirt around the obvious: the 1090T can be had for $300. That leaves you with $700 to outfit the rest of your system, before even reaching the cost of Intel's chip.

If money is no object, or you're unwilling to scrimp on your top-tier workstation, Intel's six-core processor remains king of the hill. But as far as cost-effective performance is concerned, AMD's Phenom II X6 1090T is a tantalizing prospect, that brings multithreaded potential down to the masses..


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