AMD Radeon HD 7870 and 7850 GPU Previews

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As we’ve mentioned, the Pitcairn GPU powering the Radeon HD 7800 series cards is based on the Graphics Core Next (GCN) architecture and has essentially the same feature set as its higher-end counterpart (Tahiti) found on the Radeon HD 7900 series.


Pitcairn GPU Specifics

Like Tahiti and the mainstream Cape Verde GPUs, Pitcairn is manufactured using TSMC’s advanced 28nm process node. The Pitcairn GPU, however, is comprised of roughly 2.8B transistors and outfitted with a maximum of 1,280 stream processors (to Tahiti’s 2,048) arranged in 20 compute units with 64 stream processors each. Pitcairn also sports dual Geometry engines, 32 ROPs, 80 texture units, and a 256-bit GDDR5 memory interface; double-up on Cape Verde and you've basically got Pitcairn. According to AMD, the die size of the chip is a relatively small 212 square millimeters (Tahiti is 365mm2, Cape Verde is 123mm2).

Although the Pitcairn GPU powering the Radeon HD 7800 series is pared down somewhat to hit more affordable price points, it doesn’t skimp on any features. With fewer stream processors, ROPs, and texture units, and a narrower memory interface, Pitcairn's performance will be lower than Tahiti, but its feature set remains unchanged.


Sparse Grid Supersample Anti-Aliasing
 

Morhpological AA 2.0 (MLAA 2.0)

While we're talking about features, we should also mention a couple of new feature additions coming with AMD's Catalyst 12.3 beta and 12.4 WHQL drivers. When those drivers hit, Radeon HD 6000 and 7000 series owners will have access to two new anti-aliasing modes. MLAA 2.0 (Morphological AA) uses an enhanced algorithm that offers better performance and image quality than the original. A new Sparse Grid Supersample AA mode will also be made available that works with DirectX 9, 10, and 11 titles. This SSAA mode will be further updated when the Catalyst 12.3 (and newer) drivers arrive, with automatic LOD adjustments to maintain sharper textures.
 

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Sounds like AMD is on a roll with their gpus.At the $350 price point I don't think a $20 premium is too much to ask for the increase in power and efficiency that these next gen cards bring to the table vs the older cards. Whether that will hold true when Kepler arrives, whenever that is, we'll have to wait and see.

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SSAA for DX11 titles; I must be in heaven right now. Anyways, it looks to be a good deal; performance comparable to a GTX 570, the ability to crossfire these for further performance. I agree that it's not that much more powerful compared to the previous generation but the popularity of these cards will ultimately lay in the ability to buy two of these babies and crossfire them; plus they're within my price range, and that's always a plus.

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I really like new AMD Radeon 7850. It look faster than 6850. It look peferct for upgrade.for me. New 7850 and 6850 both watts of power is very close same. but the clock is bit faster than 6850.. Might get that 7850 video card for myself. BUT i am not sure about that.

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Fun fun fun. For AMD's sake let's hope they get the majority of their cards out before Keplar comes out. I have a feeling the green team is going seriously beat these babies at least in the performance end.

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