Chip maker Nvidia can be seen striding around the graphics arena, arms raised, muscles flexed after giving Intel a mighty thrashing in the first-quarter contest. Nvidia wrested leadership of the desktop graphics market from the chip giant, Jon Peddie Research (JPR) revealed today.

Intel quit Q4 2006 with a share of 37.5 per cent. By the end of March 2007, that figure had risen to 38.7 per cent, JPR's latest statistics show. Nvidia saw is share remain static, at 28.5 per cent. AMD was down, but by only a small margin: from 23 per cent to 21.9 per cent, the researcher said.

VIA and SiS both saw their shares dip, by just a few tenths of a percentage point to 6.4 per cent and 4.3 per cent, respectively.

Still, it's not all good news for Nvidia and Intel. For a start, Q1 shipments overall were well down. First-quarter shipments are usually lower than the previous quarter's but this time round Jon Peddie himself categorised the drop as a "falling with a thud": down 5.5 per cent, though shipments were up 5.3 per cent year on year.

The big problem: Windows Vista isn't yet driving sales of graphics cards, JPR said.

Desktop GPU shipments were down 4.8 per cent between Q4 2006 and Q1 2007, while laptop-oriented chip volumes were down 7.2 per cent to 23.9m units - but still 24.6 per cent up on Q1 2006, showing the ongoing rise of the notebook.

Desktop discrete GPU shipments actually rose during Q1, albeit by less than a percentage point (0.8 per cent). But if Intel was knocked into second place in the desktop chip market, it countered that loss with a solid gain in the mobile arena - up from 50 per cent to 55 per cent.

AMD fell to a 23.2 per cent mobile-market share, from 23.4 per cent, while Nvidia slipped to 20 per cent from 22.9 per cent in Q4 2006. Nvidia grew its discrete mobile share from 59.1 per cent to 60.3 per cent. AMD's segment share fell from 40.9 per cent to 39.7 per cent.