Space Engineers tries to not limit how complex worlds you can create. At certain points you will probably reach the memory limit of your system and won’t be able to add more objects, but that’s the only limit we imposed.
We need you to understand that performance depends on the complexity of your world and the configuration of your computer. Simple worlds run smoothly even on low-end computers, but a more complex world with rich object interactions could overload even high-end computers.
Performance means how smooth the game runs. It is defined by FPS (frames per second) as well. The higher the FPS rating, the smoother the game runs. 60 FPS is great, 30 is good and even 20 is OK. If the game gets below 20, you will start feeling the delay. FPS doesn’t impact the physics simulation. FPS influences only your experience and perceived smoothness.
We can’t say where the line between a simple and a complex world is drawn. Please use your judgment and experiment a lot.
The basic rule is: more objects require more computations and more memory.
To help you understand what impacts the performance, we can provide the following advice:
Space Engineers is undergoing frequent optimizations and the performance will only get better. Nevertheless, the performance will always depend on complexity.
Note: The 64-bit version can increase the amount of objects in a world almost to an unlimited number but it doesn't mean that it increases the performance. The performance will still depend on the configuration of your system.
System Requirements are available here: www.SpaceEngineersGame.com/System-Requirements.html