Can I use a PC as my DVR?
You’re probably saying to yourself, “I’ve got a spare PC and a bunch of hard drives sitting around, why spend the money on a separate recording unit, why not just use what I already have?”
You think you’ll save money by using a PC based DVR, but you won’t.
There are two types of cameras that can be recorded with a PC – standard definition (analog) cameras that connect via BNC Coax cable and IP cameras which connect via networking cable.
It is a lot easier to record IP cameras directly with a computer, but IP cameras cost about $150 each (they shoot in HD). So, if you’re starting out putting that sort of investment in your cameras, you should get the reliability of a dedicated record and use your PC as a backup.
To record analog cameras, you’re going to need a DVR card which is a device that allows your computer to accept video inputs from a BNC Coax Cable – something like this Lorex PC Card on Amazon. Just looking at the cost of that device should immediately have you throw up your hands and say “this isn’t saving me anything!”
You’re right, but besides just looking at the price, looks at the reviews as well.
Source: Why PC Based DVRs are more trouble than you think