Today the SSD has come down enough in price to start nibbling into the low end of storage for cheap laptop computers.
Small 32GB and even 64GB SSD drives are too small to be practical with Windows 10 and its frequent updates. This leaves the 128GB SSD as the smallest practical size to compete with a hard disk.
Low cost 1TB disks are spacious and make it hard for SSD drives to gain much of a foothold in the low end of the laptop market. For the price of 1TB hard disk today a user can barely get 128GB from a SSD. Moving up the price scale M.2 256GB SSD drives are now becoming more common with some machines offering a hard disk for additional storage.
128GB SSD drives are more common in refurbished laptops which came with 160GB to 240GB hard disks. Mamy such machines were retrofitted with a SSD as small capacity laptop hard disks are rather slow. 256GB SSD drives are now low enough in price to become an attractive retrofit.
Larger capacity SSD drives are now lower in price which make them attractive for upgrades. We bought a 480GB SSD for a mobile machine which offers capacity normally seen with a hard disk. The prices for larger capacity SSD drives have come down considerably. We SSD prices to continue to decline.
The recent Lenovo 330 series laptops come with hard disks which is typical in 2018. Next year we may see more SSD drives installed in M.2 slots as new machines are sold and upgraded.
Many desktop gaming rigs have used SSD drives for Windows to be able to boot the machine faster. Hard disks are far larger in capacity which makes it hard for SSD drives to penetrate the market easily. The 480GB SSD however is large enough to be practical for a gaming box.