In simplest terms, big data is any sum of data that is too big for your current systems to handle. If you have to invest in more or better computers, it’s big data. If you have to change how you deal with your data, it’s definitely big data. If you want a number, big data usually starts at about 1 terabyte.
Changing the RAM, motherboard, or CPU does not inherently damage any data on your computer. But, when you change components on a computer, it is sometimes necessary to reinstall the operating system, and that can put data at risk. Moreover, the data risks attached to each of these changes vary considerably.