BB Bold :: 9900 Wont Go Out Of Endells Loop

i bought a 9900 and i used it for a month, however one day the blackberry wont turn on and the only thing that do was blink the red light for ten seconds. i read a lot and try getting out of the endless loop using JL Cmder and Loader, however the device keep doing the same thing over and over, even when im in Loader, it doesnt show any sympton in the screen [it keeps black all the time]. i was wonder if someone could help, or this was a good way to spend $500 dollars in nothing.