Repairing bricked Samsung T879 is easy with the RIFF Box. The device is based on the Qualcomm APQ8060 chipset.
Note, one simple way to connect over JTAG – connect USB cable to PC and
insert battery. In this case phone is automatically powered on.

To resurrect Samsung T879:

• Solder JTAG cable to Samsung T879 JTAG pads;
  
• Connect USB cable to phone and PC;
  
• Insert battery;
  
• Make sure Samsung T879 is selected in the list of models;
  
• Click Resurrect button;
  
• Wait till software signals a successful operation completion;
  
• Disconnect USB cable, de-solder JTAG wires;
  

Now phone is in bootable condition, that is, even if it does not
start up normally, you can flash it using original Samsung downloader
software to restore it to the working state.

To enter download mode:

• Disconnect PC cable;
  
• Insert battery;
  
• Hold ‘Volume Down’ key and press Power-On.
  

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