A lot of people didn't notice this, but its really simple.

Go to Sonic Generations in your Steam Library, right click it and click "Configure".
Once the program opens, Go to Graphics Configuration.
Set the options to those that follow:

• Resolution: 800 x 600 @ 60Hz
  
• Antialiasing: None
  
• Display Mode: Letterbox (DO THIS FIRST SO THE RESOLUTION IS SELECTABLE)
  
• Shadow Quality: Low
  
• Reflection Quality
  
• V-Sync: Off

The thing a lot of people didn't realize is the Resolution, which is extremely surprising.

It should look like this:

It won't do much but lower the visual quality.


Some stages such as Seaside Hill and Sky Sanctuary can lag at certain points.

This application will allow you to change certain options you can't do in the Sonic Generations Configuration such as Triple Buffering and Force VSync.