How Bigger Hard Drive Do I Need?

Other than you there is no one else on earth who can suggest you to buy a hard drive that can fulfill your requirement. So it is only you who is the person to take the decision about the capacity of the hard drive that is needed for your computer. But you have asked the question so certainly you need some help and it is our duty to provide you a help. So some tips can be suggested that can help you in taking decision about the capacity of your hard drive.
       
If you want to keep movies in your computer they take a lot of space so in that case you need a hard drive of large capacity. But for the documentation process a personal computer with a twenty gigabyte hard drive is good enough and you don't need to go for more.

One hour of high quality video of size = 9 inch diagonal requires about 1GB (one gigabyte or 1024 megabytes). One hour of high quality audio requires 650MB (megabytes) but if you want high quality video of larger screen size, multiply accordingly. For HDTV, multiply by further 3.

In general, go for at least one 512GB Hard Disk. If you want twice the speed, go for 2 HDDs striped volume at hardware level. You don't need to buy a too large HDD because prices are always coming down. If you are going to buy a laptop then it is usually hard to upgrade its components later on so buy as much as you can the first time around.