I think the !! and ?? keys on your keyboard are stuck...
But seriously, which operating system are you currently using? And which graphics card? DX10 and 11 will only run on the proper combination of hardware and software.
I used windows 7 ultimate 32bit, with hd4850.
I played almost all games with dx10 support, but not seen any big difference except for crysis.
And yes, my keyboard had a little ache