Hi Conrail,Most modern hard drives used in home PCs now are SATA. Just make sure you replace it with a HDD with "High" RPM. Aim for one with 7200 rpm. You can Also go for a Solid State disk, The offer faster access speed but are a lot more expensive.
Surface Pro 4 UK release date, price and specs: Thinner, lighter, faster with new Type Cover and Pen