Jasper (AI Guide)

Prerequisites

Before starting, gather these tools: JR Programmer (for NAND reading/writing), Xbox 360 Opening Tool or equivalent, T8 & T10 Security Torx screwdrivers, HY883 Thermal Paste, AMTECH NC-559-ASM Flux (or equivalent), and 60/40 Tin Lead Solder. You'll need a low-wattage soldering iron (15-30W), 30 AWG solid core wire (e.g., Kynar wire), and a PC with JRunner with Extras software (Github Repository). A USB drive is required for dashboard updates and homebrew installation. Store NAND backups on an external drive. Verify your Xbox 360 boots to the dashboard before proceeding. Soldering experience is recommended, as Jasper's solder points are small and delicate.

Overview

The Jasper, manufactured between 2008 and 2010, is the most reliable Xbox 360 Phat model, featuring a 65nm GPU and improved cooling for minimal Red Ring of Death (RRoD) risk. It comes in 256MB or 512MB NAND variants (check for memory unit slots on the console's side) and always includes an HDMI port. Jasper is ideal for RGH 1.2 using the CoolRunner Rev C chip, offering fast boot times (5-30 seconds) and high consistency for running homebrew, emulators, or game backups.

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How to Identify

• Manufacture Date: Check the serial number sticker on the back for a date between 2008 and 2010.
• Power Socket: Requires a 150W PSU (12V, 12.1A). Confirm by checking the power socket on the back of the console.
• Memory Chip: Features 256MB or 512MB internal NAND storage, indicated by memory unit slots on the console's side.
• HDMI Port: Always present on Jasper models.
• CB Version: Check in JRunner after NAND dump; Jasper typically has CB 6750-6754, exploitable for RGH 1.2.

Before You Take the Xbox Apart

Ensure your Xbox 360 is on dashboard version 2.0.14719.0 or later for RGH 1.2 compatibility. Download the update from Microsoft's official website or transfer it via a USB drive. If the console is already modded, avoid updating via Xbox Live to prevent overwriting hacks. Use T8 & T10 Security Torx screwdrivers for disassembly, and test the console to confirm it boots to the retail dashboard. Back up game saves and profiles to a USB drive.

NAND Read/Write Wiring

Using the JR Programmer, 60/40 Tin Lead Solder, and AMTECH NC-559-ASM Flux, solder 30 AWG solid core wires to the NAND points on the Jasper motherboard, as shown below. Use a low-wattage soldering iron (15-30W) to prevent board damage and ensure clean joints without solder bridges. Apply Kapton tape or electrical tape to insulate wires and prevent shorts.

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Connect the JR Programmer to your PC and launch JRunner with Extras. If JRunner detects the Xbox version (e.g., "Jasper 256MB" or "Jasper 512MB"), proceed to read the NAND. If detection fails, use a multimeter to check for loose connections or cold joints, ensure drivers are installed, and verify the JR Programmer is seated correctly.

Reading the NAND

In JRunner, click Read Nand to extract the console's firmware and console-specific data. JRunner performs two reads to verify accuracy, saving the NAND file to the Output folder. If the reads don't match, check soldering, USB connections, or update JRunner to the latest version. Save at least two backups of the Output folder to an external drive, naming them clearly (e.g., "Orig_NAND_Jasper.bin"). Test the console to ensure it boots to the retail dashboard before proceeding.

Installing the CoolRunner Rev C

Using the Xbox 360 Opening Tool, remove the X-Clamps to access the motherboard. Install the CoolRunner Rev C chip near the southbridge, above the USB/Ethernet shields, as shown below. Solder 30 AWG solid core wires with 60/40 Tin Lead Solder and AMTECH NC-559-ASM Flux to connect PLL_BYPASS, RST, and CLK points. Apply HY883 Thermal Paste to the CPU/GPU when reapplying heatsinks. Set the chip's jumpers to "Phat" mode and bridge the CAP for consistent boots. The CoolRunner Rev C ensures reliable RGH 1.2 boot times (5-30 seconds).

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Programming the Chip

Connect the CoolRunner Rev C to your PC via the JR Programmer. In JRunner, select the "RGH 1.2" tab, choose your motherboard (Jasper 256MB or 512MB), and click Program Timing File. Use timing file 21 (7.2-7.3ms delay, ~349,821 cycles @ 48 MHz) for Jasper. If boot times are slow, try alternative timings from Octal450's timing files pack. After programming, set the CoolRunner switch to "NOR" and disconnect the programmer. Verify connections with a multimeter to ensure no shorts.

Writing the NAND

In JRunner, load the NAND dump and click Create XeLL to generate a bootloader for homebrew. Click Write XeLL to flash it. Boot the Xbox into XeLL (blue screen) by pressing the eject button; the CPU key will display on-screen or via network connection. Enter the CPU key into JRunner'sCPU Key field to validate it. If valid, select dashboard version (e.g., 2.0.17559.0), click Create XeBuild, and then Write Nand to flash the hacked dashboard.

Test the console: it should boot into XeLL with the eject button and the custom dashboard (e.g., Aurora or Freestyle) with the power button. If using a stealth server for online play, install it via USB after flashing.

Troubleshooting

Console Doesn't Boot to XeLL: Check CoolRunner wiring, ensure jumpers are set to "Phat," and verify timing file. Reflash XeLL if needed.

JR Programmer Fails to Detect NAND: Inspect solder joints with a multimeter, test USB connections, update drivers, and try a different USB port or cable.

Slow Boot Times: Adjust CoolRunner timing in JRunner (try files 20-22) or clean solder points for better contact.

Console Bricks: Restore the original NAND backup using JRunner'sWrite Nand option.

Resources

Join modding communities like Se7enSins (Se7enSins) for support. Download JRunner, XeLL, and XeBuild from trusted sources like Octal450's GitHub (Github Repository). Verify dashboard updates from Microsoft's official website (Xbox Support). Always use reputable sources to avoid malware.