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AMD's Young Turks - Radeon HD 6670 and 6570

AMD's Young Turks - Radeon HD 6670 and 6570

It Ends with the Turks

It Ends with the Turks

And it's done. Six months after AMD launched the first member of its Northern Islands GPU family, Barts, in the form of the Radeon HD 6850 and 6870, the last GPU for this generation, Turks has been introduced. Released as the Radeon HD 6670 and Radeon HD 6570, Turks is aimed at the entry level segment, which also means that AMD has refreshed its entire range of graphics cards, from the highest tier enthusiast product, the dual-GPU Radeon HD 6990, to the lowest Radeon HD 6450 (released initially as an OEM part).

As their model names suggest, the Radeon HD 6670 and 6570 are designed to replace its Redwood-based predecessors, the Radeon HD 5670 and 5570. Given the mostly similar architectures between the Northern Islands and Evergreen GPU families, the Radeon HD 6670 and 6570 represent a slight boost in performance over the previous generation. An additional SIMD engine ensures that the Turks get 80 more stream processors and four more texture units, along with the various updated technologies found on the Radeon HD 6000 series, like UVD3, HDMI 1.4a and stereoscopic 3D support.

The core clock on the Radeon HD 6670 also gets a slight increase to 800MHz from 775MHz, though the Radeon HD 6570 remains unchanged from the 5670 at 650MHz. The memory bus remains the same at 128-bit, with similar 1GHz base memory clock on both the 6670 and the 5670 (which results in 4000MHz with GDDR5 memory). The 6570 also gets the GDDR5 option, which would be an improvement over the 5570's DDR3 default. As a result, we expect a significant performance gulf between the 6570 and the 5570, especially when it comes to memory bandwidth.

With both series on the same 40nm manufacturing process from TSMC, the additional SIMD engine, while providing a performance increase, does imply a slightly larger die, and one can expect a correspondingly minor jump in TDP and power consumption.

We didn't quite manage to get the Radeon HD 6450 when it was first launched a couple of weeks back, but we do have it now and we've also included this most basic and low-end of the Radeon HD 6000 series as part of this feature. With a different core, Caicos, the Radeon HD 6450 is a far cry from the Turks, with just 160 stream processors and just eight texture units. A 64-bit memory bus completes its entry level specifications and while GDDR5 versions are available, the memory bandwidth by itself won't produce any miracles. On paper, the 6450 has twice the stream processors as the previous 5450, which some of you may know, is now finding new life as part of the Brazos platform. It should help the newcomer differentiate itself from the 5450, but it will face an uphill task convincing users that it's more than just integrated graphics.

It's a lot to take in, so after our 'glamor' shot of the three new Radeon HD cards below, we have our usual table comparing the specifications of these GPUs, together with some of its probable competitors, both old and new. We recommend expanding the page view mode to 100% to view the table  comparison in proper.


The Sub US$100 Segment
Model AMD Radeon HD 6670 AMD Radeon HD 6570 ATI Radeon HD 5670 ATI Radeon HD 5570 NVIDIA GeForce GT 520

NVIDIA GeForce GT 430

ATI Radeon HD 6450

ATI Radeon HD 5450
Core Code Turks XT Turks PRO Redwood XT Redwood PRO  GF119 GF108  Caicos Cedar PRO
Transistor Count 716 million 716 million 627 million 627 million  Unknown 585 million  370 million 292 million
Manufacturing Process 40nm 40nm 40nm 40nm  40nm 40nm 40nm 40nm
Core Clock 800MHz 650MHz 775MHz  650MHz  810MHz 700MHz 625 - 750MHz 650MHz
Stream Processors 480 Stream Processing Units 480 Stream Processing Units 400 Stream Processing Units  400 Stream Processing Units  48 Stream Processors  96 Stream Processors  160 Stream Processing Units 80 Stream Processing Units
Stream Processor Clock 800MHz 650MHz 775MHz  650MHz  1620MHz  1400MHz  625 - 750MHz 650MHz
Texture Mapping Units (TMU) or Texture Filtering (TF) units 24 24 20  20 8  16  8 8
Raster Operator units (ROP) 8 8 8 8  4  16  4 4
Memory Clock 4000MHz GDDR5 4000MHz GDDR5 / 1800MHz DDR3 4000MHz GDDR5 1800MHz DDR3  1800MHz DDR3  1800MHz DDR3  1066 to 1600MHz DDR3 / 3200 to 3600MHz GDDR5 1600MHz DDR3
DDR Memory Bus 128-bit 128-bit 128-bit 128-bit  64-bit  128-bit 64-bit 64-bit
Memory Bandwidth 64GB/s 64GB/s / 28.8GB/s 76.8GB/s 28.8GB/s  14.4GB/s 28.8GB/s

 8.5 to 12.8GB/s (DDR3) / 25.6 to 28.8GB/s (GDDR5)

PCI Express Interface PCIe ver 2.1 x16 PCIe ver 2.1 x16 PCIe ver 2.0 x16 PCIe ver 2.0 x16 PCIe ver 2.0 x16  PCIe ver 2.0 x16  PCIe ver 2.1 x16 PCIe ver 2.0 x16
Molex Power Connectors None None None None None None None None
Multi GPU Technology CrossFireX CrossFireX CrossFireX CrossFireX None None None None
DVI Output Support 1 x Dual-Link 1 x Dual-Link 2 x Dual-Link 2 x Dual-Link 1 x Dual-Link  2 x Dual-Link  1 x Dual-Link 2 x Dual-Link
HDMI 1 (ver 1.4a) 1 (ver 1.4a) 1 1 1 1 1 (ver 1.4a) 1
DisplayPort 1 (ver 1.2) 1 (ver 1.2) 1 1 None None 1 (ver 1.2) 1
HDCP Output Support Yes Yes Yes  Yes Yes  Yes Yes Yes
Street Price Launch Price: US$99 Launch Price: US$79 ~US$70 - 85 ~US$50 - 75  ~US$60 ~US$70  ~US$55 ~US$55


Among the cards compared above, we have of course previously covered the Radeon HD 5670 and 5570. You can find out more about these budget cards here. As for the newer GeForce GT 520, it has been around, but in the form of the mobile GPU 520M. Given that it was released shortly after AMD introduced the Radeon HD 6450, one can speculate that NVIDIA brought it out in retail to match the 6450, especially when their suggested retail prices differ by just US$5. On paper, it looks like the successor to the GT 220, but not in a good way; the specifications look as weak and at times, even worse than the 220. You can compare the specs for the GeForce GT 520 listed above with the old GeForce GT 220 listed on this page.

We'll be testing the GT 520 along with the other new Radeon HD cards, but the focus for the day remain AMD's Turks and Caicos.