Nvidia shield tablet optimizing apps and reboot loop

[CU]

My son's tablet will not startup anymore. It tries to start, but goes into optimizing apps. The when done with that it displays the nvidia logo for a awhile before it restarts and starts the same process over. I have went to recovery mode and wiped the cache and removed the sdcard. Is there anything else to try before I wipe the tablet and he loses all his saved games?