How my setup works, may be different for you:
-Right-click on the desktop screen
-Choose NVIDIA Control Panel
-In left panel, select Manage 3D Settings (should default to that)
-In right box, there are two tabs: Global Settings and Program Settings; choose Program Settings
-Click Add, then search for the MLB 2K12 .exe game launcher (in main game folder; already told you where to find that)
-Once the .exe is added to the list, you can customize video card settings for that one game
-Check the CUDA-GPUs setting; use the dropdown tab to make sure the box listing your video card is checked (means the card is active and working for that game)
When customizing the video card for MLB 2K12, I suggest you begin by shutting off all filtering and aliasing options. Play the game with the minimum settings to see how it runs/looks. Then try turning on individual settings one by one, checking to see if/how each new setting improves performance/appearance. It will take a while, but you should eventually come up with an acceptable balance of settings that both looks okay and allows you to play the game without too much slowdown.
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