Based on the new Turks GPU, AMD’s Radeon HD 6570 and 6670 graphics cards are poised to hit the $80-$100 market. Do these products have what it takes to compete in this fiercely competitive segment, or are AMD's subtle evolutionary changes too small?

For the third time this month, we’re reporting a graphics card launch from AMD. And this time it’s a double-header. Meet the Radeon HD 6570 and 6670:

These new products are a natural evolution of the Radeon HD 5570 and 5670, two very important cards in the sub-$100 graphics card market. For some time, we’ve recognized the Radeon HD 5570 as a realistic ~$65 starting point for budget buyers looking for respectable gaming hardware, and the ~$80 Radeon HD 5670 holds the distinction of being the most powerful reference design that doesn’t require a dedicated PCIe power cable.

To this point, most of the Radeon HD 6000-series cards employ a subtle (but notable) architectural tuning from the 5000-series days, so we expect these new models to be closely related to their predecessors. Let’s see how the Turks GPU stacks up:

This is another offspring of the Barts graphics processor introduced in the Radeon HD 6800 series, which itself was an evolution of Cypress. This one is scaled down to six SIMD engines, though. Each engine is associated with four texture units and is composed of 16 thread processors, with five stream processing units (ALUs) per thread processor. In the case of Turks, that makes for a grand total of 24 texture units and 480 ALUs. Two 64-bit memory controllers deliver an aggregate 128-bit memory interface, and both render back-ends host four color ROPs, totaling eight.

Turks sports the same features found across the entire Radeon 6000 line: improved tessellation performance, Eyefinity enhancements (these particular models support up to four displays), and Blu-ray 3D decode acceleration. At least for now, you'll find this GPU in two specific configurations: Radeon HD 6570 and 6670. Let’s consider where they sit in the grand scheme of things:

From this chart, it's particularly clear that Radeon HD 6570 and 6670 are simple evolutionary steps from Radeon HD 5570 and 5670. Though those cards share the same specifications per SIMD engine, the new models sports six (instead of five), resulting in 80 more ALUs and four more texture units. The Radeon HD 5570 and 6570 share the same clock rates; Radeon HD 6670 gets a 25 MHz core boost over the 5670. As a result, we expect the Turks-equipped cards to demonstrate a lead over their predecessors when it comes to performance, even if the advantage isn't particularly pronounced, given the identical ROP count and 128-bit memory interface.

While we don’t expect much from the similarly-priced GeForce GT 240 (a card with lower performance than the Radeon HD 5670), the GeForce GTS 450 can be found kissing the $100 mark, promising stiff competition for the new Radeon HD 6670 and its $99 MSRP. With double the CUDA cores and ROPs of the GT 240, Nvidia's GeForce GTS 450 is a serious player. But before we see how these entry-level cards fare in combat, let’s have a look at AMD's Radeon HD 6570 and 6670 reference hardware.