The Radeon HD 4890 card aside, AMD isn't very fond of partners overclocking its graphics card from factory. This is also why we haven't seen any factory overclocked version of Radeon HD 4770 yet. ASUS intends to change this as it has announced two different models of the new mid-range card. ASUS EAH4770/HTDI/512MD5 is the standard model, which is pretty much the same as the reference, but ASUS EAH4770 TOP/HTDI/512MD5 comes with overclocked GPU and memory out of the box.

ASUS' Top model sports a GPU frequency of 800MHz and 3.4GHz memory clock, a marginal increase from the reference frequencies; 750MHz and 3.2GHz. But it has been blessed with ASUS Voltage Tweak technology, recognized from the HD 4890 series.

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