Use the Team Xecuter PRO RROD Kit, follow the instructions properly and you will get it back to life.
Dont mess about with towels or overheating the box - just take it apart, clean it up (dab of isopropyl), replace the heat sink bolts/pads - apply thermal paste - run it with the fans disconnected for a few mins to allow it to reflow and your be back up and running.
Start to finish 30 mins at most for a first timer .