Graphics artifacts and limited mouse movement

When in game, graphics artifacts start to appear and then get progressively worse. They seem to be centered above moving heroes, but the artifacts cover most of the screen. About mid game, I lost the ability to move the cursor to the bottom portion of the screen. This problem remained in the program, even after the game was over. Made the game virtually unplayable.

post your DXDiag


paste your DXDiag like this:

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DXDIAG
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