Ever since they launched back in October of last year, ATI's 5xx0 series of cards (codename Evergreen) have been dominating the graphics market. Their combination of class-leading performance, features, and power consumption along with support for DirectX 11 has meant they were the clear choice for anyone looking to buy a new card in the last six months. Now there's a new addition to the roster, the mid-range HD 5830.
Based on the same RV870 chip (Codenamed Cypress) that sits at the heart of the HD 5870 and HD 5850, the HD 5830 uses those chips that haven't quite met the strict manufacturing demands of these high-end cards. By shutting down malfunctioning portions of the chip, you still get a working card but with reduced performance. This is the same approach as used on the HD 5850 cards, though more of the chip is disused is this new card.
In particular, the HD 5870 has 1,600 stream processors and 80 texturing units (collectively split up into 20 SIMD blocks) accompanied by 32 ROPs. For the HD 5850, as well as having lower clock speeds, one of the SIMD blocks is disabled resulting in 1,440 stream processors, 72 texture units, and 32 ROPs. As for the HD 5830, it has six of the SIMD blocks disabled and half the number of ROPs, though it does retain the 256-bit memory interface as the other cards. In contrast, the HD 5770 uses a completely different chip and has 800 stream processor, 40 texture units, 16 ROPs, and a 128-bit memory interface. The upshot is we expect the HD 5830 to have performance that sits somewhere between the HD 5770 and HD 5850.
Conversely, the card we received for review looks nothing like one that should sit somewhere between the HD 5850 and HD 5770. Instead it's a reference (i.e. made by ATI itself) HD 5870 board with a 5830 chip stuck on it and as such it's long (284mm/11.2in) and heavy (975g).
However, fear not because board partners have been given carte blanche to design their own boards and cooling solutions so are producing much shorter and lighter variants for final retail – though some are still using the same long board so watch out for those. As such, while this card's cooler proved impressive in our sound level tests, it isn't necessarily going to be a reflection of what you get from a shop bought card.