Bricked EVO 4G LTE

[Jason Asana]

I have a EVO 4G LTE, unlocked. The screen doesn't turn on. I can only get to the bootloader but only when plugged in to the computer. My computer installs device but doesn't recognize my phone when done. Can someone give me a step by step instructional on how to get back to stock? I am a noob.

Other info about my phone:
Jewel
S-ON
Radio- 1.12.11.1210

 

[Caleb Morris]

When plugged into your computer, does your bootloader have the phrase Fastboot USB or just Fastboot?

 

[zhecht]

How did it get into this state? Did you flash or install something first?