Problem #1 : [Prototype PC Error] Black Screen / Input not supported / Blackscreen on Prototype start up.
Solution :
For Windows XP Users
1. From the start menu, Click on Run then type “dxdiag”
2. Click on the “More Help” Tab then click the “Override Refresh Rate” Button.
3. Set the refresh rate override value to 60
For Windows Vista Users
1. Run dxcpl.exe from the Directx SDK folder
2. Click on the “Directdraw” tab then set the refresh rate to 60.
Credits : Panopticon and Kaserei, Activision Prototype Forum
Essaye, j'ai trouver ça sur internet l'autre fois, au cas ou j'aurais eu un probleme 
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