If you have a really old computer that you wish could be used to play modern battle royale games, but just can't quite handle even the lower end settings, PUBG Lite would be the answer to your prayers. Unfortunately, for now that's only if you live in Thailand.
PUBG Lite is a new free-to-play version of PlayerUnknown's Battlegrounds, designed with low-spec PCs in mind. The game is available in open beta right now, but currently only in Thailand. According to the announcement for PUBG Lite it will eventually come to other regions, but we suspect that's likely just referring to other territories within Asia, where internet cafes are more popular and the F2P model is much more entrenched.
Both the Miramar and Erangel maps are included in the port, which has recommended specs that line up with the lowest specs on the main version of the game. If you can trick your PC into thinking it's on an internet connection in Thailand, of course, you could always try playing on your potato PC right now.