Microsoft's long-awaited launch of Windows 8 in October brought touchscreen features to laptops but failed to spark a resurgence in sales that Nvidia and other PC chipmakers and manufacturers had hoped for. Nvidia's traditional PC graphics chip business, which accounts for most of the company's revenue, grew 7 percent versus the year-ago quarter after the company gained market share. Nvidia's Tegra 3 mobile processor is used in Google's ( GOOG ) Nexus 7, one of only a handful of tablets to make inroads against Apple's ( AAPL ) iPads. The Tegra 3 chip is also used in Microsoft's Surface Windows RT tablet. But some analysts worry Nvidia may struggle to maintain growth with new design wins for its upcoming Tegra 4 chip as competition increases. Nvidia's Tegra group, the bulk of which comes from Tegra sales, grew 90 percent, year over year, to $208 million.