The market share of Windows 10 is not growing at the pace expected, and after the initial impulse of this new version of the operating system things have calmed down. It seems that many users can not find enough reasons to upgrade, but Microsoft want to make some pressure and this will limit the time you can buy PCs with older versions of Windows.
This applies to the sale of PCs with Windows 7, which can only be purchased (if the manufacturer gives you that option) until 31 October 2016. So if you want access to this operating system based computers, will have to weigh over the next 12 months. After that Microsoft does not allow manufacturers to offer that option.
In a year you have to follow only the updates :
The new page dedicated to the life cycles of different versions of Windows has been updated to reflect these new dates on which they will stop selling PCs with Windows pre-installed on it. Windows 7-based computers will stop selling in October 2014. However the criticism that Microsoft Windows 8 did extend the deadline for the sale of such equipment.
Yes, although OS no longer be sold, the period of support remains. All versions of Windows 7 will continue receiving security updates through the extended support period, which ends on January 14, 2020. Windows 8.1 retains the normal support and extended support period will begin on January 9, 2018 and ending on 10 January 2023. From that date the operating system will no longer receive security updates.