Hig41uatx Rev 11 Schematic Page
You will likely find that the official service manual, and especially the board's schematic, has never been made available to the public. This is common for several reasons:
If your motherboard is completely unresponsive or stuck in a boot-loop, use a digital multimeter to trace these foundational power states across the board layout: Power Rail Target Component Common Schematic Measurement Point CPU VRM Phases Input high-side MOSFETs near LGA 775 Socket +5V_SYS USB Ports & Logic Pins 4, 6, 19, 20 on the Main 24-Pin Connector +3.3V PCI Slots / Chipset Logic Pins 1, 2, 12, 13 on the Main 24-Pin Connector +5V_SB (Standby) Super I/O & Power Button Pin 9 on 24-Pin (Must read 5V even when system is Off) VCC (1.8V - 3.3V) SPI Flash ROM (BIOS Chip) Pin 8 of the 8-pin BIOS Flash IC Common Diagnostic Scenario: Dead Flash ROM Rail hig41uatx rev 11 schematic
Most motherboard failures stem from power delivery issues. The HIG41UATX Rev 1.1 relies on several critical voltage steps to transition from standby mode to a fully operational state. 1. Standby Power (+5VSB and +3.3VSB) You will likely find that the official service
| Category | Specification | | :--- | :--- | | | Foxconn H-IG41-uATX | | HP/Compaq Name | Eton / EtonL | | Form Factor | Micro-ATX (24.5 cm x 24.5 cm / 9.6" x 9.6") | | Chipset | Intel G41 Express | | Socket | LGA 775 (Socket T) | | Front Side Bus | Supports 1333/1066/800 MHz | | Memory (RAM) | 2 x DDR3 DIMM slots (240-pin) Supports up to 8GB of non-ECC, unbuffered DDR3 memory Speeds: DDR3-1333 / 1066 / 800 | | Integrated Graphics | Intel GMA X4500 (VGA port on back I/O) | | Expansion Slots | 1 x PCI Express x16 2 x PCI Express x1 1 x PCI 1 x PCI Express x1 minicard socket | | Audio Codec | Realtek ALC662 (6-channel HD Audio) | | Network (LAN) | Realtek RTL8103EL (10/100 Ethernet) | | Internal Connectors | 1 x 24-pin ATX power connector 1 x 4-pin ATX power connector 4 x SATA 2.0 (3Gb/s) connectors 2 x 12V fan headers (CPU & system) 1 x 9-pin header (Power/Reset/Power LED/HDD LED) 2 x USB 2.0 headers (supporting 4 ports) 1 x 9-pin audio header 1 x SPDIF out header | | Back I/O Ports | 1 x VGA port 4 x USB 2.0 ports 1 x RJ-45 LAN port 1 x Line In (light blue) 1 x Line Out (lime) 1 x Microphone (pink) | | CPU Support | Core 2 Quad, Core 2 Duo, Pentium Dual Core, Celeron (95W Max TDP) | Core 2 Duo
: The Southbridge releases sleep states to enable main system power rails ( +12V , +5V , +3.3V ).