The functionality of any software depends on the quality of the computer. Especially when it comes to restaurants and supermarkets, where a lot depends on the computer and it gets far more loaded than usual home PC. A restaurant computer does work continuously during hours, that's why is it necessary to carefully choose its parts because their quality means the computer will work fast and safe.
According to our experience, we suggest you properties of optimal PC:
As for monitors, the brand is not crucial here. You can use Samsung, Philips, Sony etc. It's necessary a monitor resolution to be min 1366x768 (pixels). You can choose any mouse and keyboard you like. You can also buy CD-ROM, if neccessary.
These are minimal requirements. When a restaurant needs a new computer we suggest to them optimal features, which costs less than something like a supercomputer and its stunning features, which is useless for the restaurant software. Although you can buy or use your own PC that has better specifications than we suggested above. It's up to you.
Of course, it doesn't mean that a PC with different specifications can't be used for work. It means that it might be less reliable and safe.