Game running slow

Try to lower down your settings at dead space 3 - video settings most especially. Lower some of it or disable some of the settings - play around with it to find what suits you best. Also are you running other heavy programs that uses RAM? ex. Adobe Creative Suites or chrome with lots of open tabs? you can also check it by running the Task Manager and find those that eats up your RAM aside from the game.
 

Its already at low graphics still not working
 
Are you running on wall power? Power Management settings set to high performance? What exactly is "too slow" what FPS are you getting? Do other games and benchmarks run OK?