AMD and NVIDIA are the only two companies who are in the consumer discrete graphics card market in a big way. There are some other much smaller companies but these are the two leaders. For a long time now, NVIDIA has held the lead in discrete GPUs.
AMD has taken lots of flack for buying ATI as the GPU company has had a hard time in the market over the last few years and poor profits cause AMD to have to take some losses on its new GPU division. AMD is now bragging that for the first time in four years, since the purchase of ATI in 2006, AMD has taken the market lead in discrete GPUs from NVIDIA.
AMD now holds 51.1% of the discrete GPU market with a growth of 10.4 points from Q2 2009. All of that growth came directly from NVIDIA who lost the same exact amount of points. AMD also has 56.3% of the mobile discrete GPU market. I wonder what NVIDIA will do to get that market share back.