Even more old school than Dex, the Hideo Kojima-led Snatcher may be one of the very first graphical cyberpunk games to hit consoles. This forgotten gem was released in Japan back in '88 and then eventually hit North America with a Sega CD port in '94.
Snatcher is basically made of classic tropes, but that's because they were still fairly new at the time. The amnesiac investigator on the hunt for androids who look like humans will make you think alternatively of Terminator or Blade Runner.
On the gameplay front, Snatcher sits somewhere between a point 'n click adventure game and a visual novel — but good luck finding a working copy at this point! Your best bets are going to be abandonware sites, trying to get a Sega CD emulator up and running, or just watching full Let's Plays over at YouTube.