I am considering adding storage space to my Dell Optiplex 755. I don't know much about this except I assume it involves either plugging something into the motherboard or using a desktop unit that plugs in through a USB port. I am going to be doing some video editing and I need space for all my footage. This is a separate concern from data backup, for which I plan to acquire two external hard drives (which I asked about in another thread). What is the best way to go about this? I am already worried about external hard drives' rate of failure. Is it any better for internal hard drives/internal SSDs/desktop additions? Obviously this includes the added consideration that I will be working off the unit every day for about 8 hours, so it has to be hearty enough to deal with that. Thank you for any advice!