Postby strupEX » Wed Apr 22, 2020 10:25 am
One thing that might be the casue for your problem is the operating system itself. When I first started playing this game back in 2015, I had a pretty old PC with a 50hz Monitor, 32bit Windows 7 SP2 and some early 2000's specs like a GeForce 8400GS.
Everything worked without any issues.
When I build my high end PC, I suddendly experienced lag and frame skips. The game was pretty much unplayable.
However I fixed it by changing the OS compatibility
Maybe set down the amount of CPU threads that work for this problem in the task manager. (maybe by only 2-4)
Set the priority to "higher than normal" and check if your GPU is active.
If you have a high refreshrate monitor, try downgrading it to 50-60Hz (60Hz recommended).
Close programs that have a potential high RAM usage.
Last thing, try to edit the compatibility in properties and select an older OS.
Do each of these steps individually or comined and it might fix the problem.
If none of these tips help you, I really recommend you to play the highly improved sequel (or upgrade) SMBX2. This version can read all of your older files made in the original and runs permanently at 65fps instead of just 60.