Xbox 360:GPU Retrofit

This page is intended for advanced technicians only. If you do not have advanced component and BGA rework skills, you will not be able to complete the process successfully.

Some GPUs can be retrofitted onto earlier boards. This page contains instructions for what changes need to be done in order for the retrofit to work.

Falcon

Both variants of the Jasper 65nm GPU can be retrofitted onto a Falcon motherboard. (Demo Video)

Guide By: Octal450

Instructions

GPU Table

Name	Part Number	GPU/eDRAM Lithography	GPU/eDRAM Temp Target
Zeus	X817793	65nm/80nm	71C/73C
Kronos1	X820894	65nm/65nm	73C/75C

Install GPU

• Replace 80nm U4D1 with 65nm

Set VID 1.075V

• Remove 0 ohm R8B9
• Remove 0 ohm R8B10

Set FSB/PCIe/Memory Calibration

• FSB:
  • Install 40.2 ohm R4R9
  • Remove 4.87K ohm R5R3
• PCIe:
  • Remove 1.47K ohm R4R3
  • Remove 562 ohm R5D1
  • Replace 2K ohm R5D2 with 49.9 ohm
• Memory:
  • Replace 40.2 ohm R4R8 with 240 ohm
  • Replace 40.2 ohm R4T1 with 240 ohm

Tie V_GPUPCIE to V_GPUCORE

• Remove 0 ohm R4C31
• Install 0 ohm R4P13
• Install 0 ohm R4P14
• Remove IC U5C1

Modify Firmware

• Use J-Runner with Extras to dump the nand
• Change the type to Jasper 16MB, then RGH the console to get the CPU key
• Set the required XeBuild options and build the image
• Open the SMC Config Editor from the Nand menu, and update the thermal targets from the table above
• Write the nand to the console

Jasper V1

The Kronos1 GPU can be retrofitted onto a Jasper V1 motherboard. (Demo video)

Guide By: Octal450

Instructions

GPU Table

Name	Part Number	GPU/eDRAM Lithography	GPU/eDRAM Temp Target
Kronos1	X820894	65nm/65nm	73C/75C

Install GPU

• Replace Zeus U4D1 with Kronos1

Modify Firmware (Optional)

• This step is optional, Zeus targets 71C/73C, there is no harm by running the chip 2 degrees cooler
• Use J-Runner with Extras to dump the nand
• Open the SMC Config Editor from the Nand menu, and update the thermal targets from the table above
• Write the nand to the console