I purchased a GS2 back in October 2011 and the display would dim itself a couple of times a week. I always kept the display at full brightness without any power saver on. I called Tmobile tech support and was told that they never heard of this and had no records of any other complaints. I sent it back and received either a new or refurbished one about three weeks ago. Now this phone display dimmed itself today and once about a week ago. Again, no type of power saver on. Any suggestions? Thanks, Ed.