What happened to the 880 and 870? Nvidia's explanation is that they had to use the 800 series earlier this year for a new series of notebook GPUs, as large laptop manufacturers insist that they receive a series of "new" models each year, regardless of whether there are actual new chips. Most of these 800 series notebook GPUs are therefore existing chips from the Kepler generation, running at different clock frequencies than their predecessors. In order to maintain the relation between new chips and new boards, Nvidia decided to introduce the new cards as part of the 900 series.
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