The heat sink retention mechanism for the Memory Controller Hub (MCH) is a new addition to the Intel® Pentium 4 motherboards. In the rare occasion that the heat sink shifts or the retention mechanism becomes detached, move the latch to the open position, connect the retention feet to the motherboard, and then move the latch to the closed position, as shown.

Note: Use caution when reseating cards or power connections in this area as the MCH heat sink is hot to the touch.

• Intel 82845 Memory Controller Hub (MCH)
• Intel 82801BA I/O Controller Hub (ICH2)
• Intel 82802AB BIOS Firmware Hub (FWH)

The Intel 82845 MCH controls the following:

• Accelerated Graphics Port (AGP) Interface
  • Full AGP 2.0 compliance.
  • Supports 1X, 2X, and 4X AGP cards, with 1.5 volt (V) only signaling.
  • Supports 2X and 4X fast write signaling.

• Memory
  • Three gold-plated 3.3 volt (V) un-buffered DIMM slots
  • Support for SDRAM at 4-clock, 133-megahertz (MHz)/PC133 only
  • Support for 64-megabit, 128-megabit, 256-megabit, or 512-megabit memory technologies
  • Single or dual-sided un-buffered SDRAM DIMM configuration
  • Suspend-to-RAM (ACPI S3) support
  • Serial Presence Detect (SPD) 1.x or later
  • Support for type CL2 and CL3 devices