I think there a tutorial that u can use both Atm and SX on the same emmc parition.
Therefore, u can still play XCI file in docked mode using USB feature of SX.
What i meant is keep pressing Power button and Vol+ until can go to RCM mode then inject Hekate payload. then choose CFW(sysnand). After that just downgrade.
It's not dead. Just Burnt Fuses or like Dave said the SD card is in wrong format. I faced the same problem this week.
What i did were
- plugging it to the PC to detect the RCM mode via TegraRcmGUI.
- Keep Pressing Power and Vol+ several times until it go to RCM Mode
- When it go to RCM mode...