Gamers looking to spend some $250 on a brand new graphics card were given two new options last month when ATI unleashed their Radeon HD 4890 and Nvidia countered with the GeForce GTX 275.
Starting with the Radeon HD 4890, this new card is in essence an overclocked Radeon HD 4870 with far greater overclocking abilities.
ATI has fine-tuned the RV790 XT core allowing for incredible core frequencies. Although the default core speed of 850MHz is a moderate bump over the 4870, many users are reporting overclocks in the order of 1GHz and beyond, which makes for an interesting update.
The GeForce GTX 275 is also a derivative from an existing product, borrowing its GPU from the GeForce GTX 295, which is a dual-GPU graphics card.
The GTX 275 uses a 55nm GPU featuring the same amount of SPUs and TAUs as the more powerful GeForce GTX 285, while only as many ROPs as the GeForce GTX 260. Nvidia has then increased the core and memory frequencies of the GeForce GTX 275 when compared to the dual-GPU GeForce GTX 295.
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