Chip Level Computer Hardware: Power Sequence of ICH Motherboard: Part-8

Introduction

This tutorial focuses on understanding the power sequence for the ICH motherboard, specifically how to check the GMCH VTT, RAM supply, GMCH supply, and CPU core voltage. This knowledge is crucial for troubleshooting and diagnosing issues related to computer hardware, particularly in chip-level repairs.

Step 1: Understanding Power Sequences

• Familiarize yourself with the power sequence of the ICH motherboard.
• Identify the key components involved:
  • GMCH (Graphics Memory Controller Hub)
  • VTT (Termination Voltage)
  • RAM supply
  • CPU core voltage
• Recognize how these components interact and their importance in the functioning of the motherboard.

Step 2: Checking GMCH VTT Voltage

• Obtain a multimeter for measuring voltage.
• Locate the VTT test points on the motherboard.
• Follow these steps to check the voltage:
  • Turn off and unplug the computer.
  • Open the computer case to access the motherboard.
  • Power on the computer (ensure safety measures).
  • Set the multimeter to the appropriate DC voltage setting.
  • Place the black probe on the ground and the red probe on the VTT test point.
  • Record the voltage reading and compare it with the expected value (typically around 1.2V).

Step 3: Measuring RAM Supply Voltage

• Locate the RAM slots on the motherboard.
• Identify the voltage test points for the RAM supply.
• Use the multimeter:
  • Similar to the previous step, turn on the computer safely.
  • Set the multimeter to the correct voltage range.
  • Measure the voltage at the RAM supply test points.
  • Ensure the reading is within the expected range (usually around 1.5V for DDR3).

Step 4: Checking GMCH Supply Voltage

• Identify the GMCH power supply test points.
• Measure the voltage:
  • Power on the computer as before.
  • Use the multimeter to check the GMCH supply voltage.
  • Typical expected values are around 1.5V to 1.8V.
  • Compare your readings with the specifications.

Step 5: Measuring CPU Core Voltage

• Locate the CPU voltage test points.
• Follow these steps for measurement:
  • Ensure the computer is powered on.
  • Use the multimeter to measure the CPU core voltage.
  • Expected values may vary based on the CPU model but typically fall between 0.8V and 1.5V.
  • Compare your measurement with specifications to determine if the voltage is within range.

Conclusion

In this tutorial, you learned how to check the power sequence for key components on the ICH motherboard, including GMCH VTT, RAM supply, GMCH supply, and CPU core voltage. Understanding these measurements is essential for diagnosing and repairing hardware issues. As a next step, familiarize yourself with the specifications of your specific motherboard model to ensure accurate measurements and troubleshooting.