Help Start up looped HTC EVO 4G LTE problem!

[HTC EVO 4G LTE Problem]

I need help fixing this old HTC EVO 4g lte from sprint.A while back I attempted to use RUU jewel to install a new version of HTC sense that I believe wasn't supported.Now,all it does is pop up with the startup logo and then turn off.When I try to turn it back on, the keys on the bottom just flash.Any help will be greatly appreciated.

 

[James L]

Boot into fastboot and run fastboot getvar all.

Then post your results minus the imei, meid etc.