You can install the BlueStacks App Player on Windows 8.1, 8, 7  as long as the following requirements are fulfilled:
  1. You must be an Administrator on your PC. 
  2. Your PC must have 2GB of RAM/main memory. (Note that having 2GB or more disk space is not a substitute for RAM)
  3. Your PC must have 4GB  of disk space available for storing Android apps / games and their data.
  4. The drivers for your PC's graphics drivers should be updated for compatibility with BlueStacks.