Long story short: I had 2x 24" LED LCD's for ~three years directly connected to my 12-Core Mac Pro5,1 ATI Radeon HD 5770. Each had power supplies and LCD panels replaced 2-3 times, one was swapped for a new model. In May, 1 display wouldn't turn on. As the AppleCare on each was due to exp. in Oct., I called Apple Tech. To my surprise, within 24 hours they approved 2 new 27" models and refunded my AppleCare. While working last night, 1 of the displays shut down. I reset my Mac Pro's NVRAM and SMC, plugged it into another surge protector (main is a APC SMART-UPS 1500 workstation “sine wave” for Mac Pro's), connected it to my new MacBook Air, 2012 Mac Mini, let it sit unplugged over night and it will not turn on. I connected the working display to the second input on my Mac Pro and it functioned properly. My Mac Pro does not recognize the second display when it is connected. I researched APC SMART-UPS systems in case the UPS was at fault, nothing; if it were my other display and Mac would definitely be effected. I did read a lot of threads on the same issues with Apple's LED displays. I wrote the Apple rep. who approved the replacements, but I'm concerned this will keep happening, impeding my workflow. Has anyone else had this many issues with their displays? I'm very disappointed, the previous 23" CCFL LCD's lasted ~8 years each. This is unacceptable.