Had the same problem and this seemed to work. I am using an i7 laptop with an Nvidia 520m card. It seems that the onboard intel video that is used by the i7 processor when the Nvidia card is not required is the problem:
- Open Nvidia control panel, either from the windows control panel or by right-clicking the Nvidia Ge Force experience icong in the system tray (if your are running that program)
- If you are not viewing 3d settings by default, click on "manage 3d settings on the lefthand frame
- In the righthand frame you have two tabs: global settings and program , choose program settings
- In the drop down window, select Dead Space 2
- Where ist says select the preferred graphics processor for this program, choose "high-performance Nvidia processor"
- Click "apply"
This will only change the settings for this game, and will allow you to properly activate and play the game!
(at least it worked for me)