This is a well known issue with this line of laptops (333, 433, 533, 334, 434, 534, their AMD conterparts and other tightly related computers). Searching this forum will give you many results as will performing a google search on this issue. With the UX533FD I haven't been able to solve this for well over a year now. Currently I'm completely disabling sleep mode, using a black screen saver after a certain period of time and hybrination when the flap is closed. Still waiting for a solution from Asus.