Microsoft believes that Windows 10 will go on sale on July 29. Basically by purchasing a new PC with Windows 10 pre-installed on July 29 you can become one of the first customer to get new operating system. Users of Windows 7 and 8.1 might have to wait for some time until they release an update.
According to Bloomberg, a Redmond spokesperson has said that Dell, Lenovo, Acer and HP will support Windows 10 operating system.
Devices manufactures by Microsoft partners will be there in stores on July 29, so that you can purchase a new computer with Windows 10 without waiting any more.