according to http://milkyway.cs.rpi.edu/milkyway/apps.php the Mac OSX NVIDIA app for modified fit has an average performance of 704,877,187 GigaFLOPS or about 99.98% of the project total. Last time I checked the market share of Mac OSX was way lower than 99.98%, especially if one takes in account nowadays the mac computers come with intel or amd GPUs.