I've set all of the renderers to off, I've set them to on, I've turned off particles and clouds and turned them on, I've changed my render distance, I've changed from fast FPS to power saver to balanced, I've changed ALL the settings and I either get so much lag I get around 5 FPS or I get a framerate that randomly dips every time something's rendered. I only get a good, constant framerate when I'm not moving or looking around in-game.
I may not be able to get good framerates in, say Amnesia or Morrowind, but I had no idea I wouldn't be able to get good framerates in a game that has less pixels than Centipede 3D.