11 Schematic: Hig41uatx Rev
When using a PDF layout or schematic viewer for the HIG41UATX Rev 1.1, leverage search terms to quickly jump to problem areas:
The "Rev 11" designation is crucial. Schematics often vary significantly between PCB revisions (Rev 10 vs Rev 11) due to changes in VRM controller ICs, resistor divider networks for voltage identification (VID), and power sequencing logic. Using the wrong revision schematic will lead to misdiagnosed shorts and blown components.
| Symptom | Check in Schematic | Common Culprit | |---------|-------------------|-----------------| | No power (LEDs off) | +5VSB rail → I/O controller Vcc | Shorted ceramic cap on +3.3VSB | | Fans spin, no POST | PWRGD_ICH (pin 32 of ICH7) | Missing 1.05V PCH PLL voltage | | Random resets | CPU Vcore ripple → PWM controller’s COMP pin | Bad electrolytic cap on Vcore output | | No sound but audio driver installs | ALC662’s AVDD (pin 4) | 3.3V_AUDIO missing due to blown inductor | | USB ports dead | +5V_USB from APL3511A power switch | Enable pin (EN) floating due to solder crack |
RT8802A (or similar). Pins to check:
A motherboard cannot process data without a master timing reference. The HIG41UATX uses an integrated Clock Generator IC driven by a 14.318 MHz crystal oscillator.
Three 1.0µH shielded power inductors labeled L1, L2, L3.
The (also commonly known as the H-IG41-uATX or Eton ) is a Micro-ATX motherboard manufactured by Foxconn for HP and Compaq desktop systems, such as the HP 500B MT and Compaq Presario CQ3000 series . It is built on the Intel G41 Express chipset paired with the ICH7 southbridge, supporting the older but still versatile LGA 775 socket. Key Hardware Specifications hig41uatx rev 11 schematic
Power down the machine, bridge the clear CMOS jumper contacts for 10-15 seconds, and then restart the PC.
To help you quickly find the right tools, here is a summary of where to look:
Use a multimeter to confirm 12V is reaching the 4-pin CPU connector. When using a PDF layout or schematic viewer
[ LGA 775 CPU ] │ Front Side Bus (FSB) │ [ Intel G41 MCH ] ─── DDR2 / DDR3 RAM │ Direct Media Interface (DMI) │ [ Intel ICH7 Southbridge ] ├── PCI-Express / PCI slots ├── SATA / IDE Ports └── USB / Audio / Super I/O The Northbridge (Intel G41 MCH)
Finding exact proprietary OEM schematics (especially for HP/Foxconn variations) requires digging into enthusiast forums or electronic repair databases. Technicians frequently use document repositories to find the PDF files necessary for board-level repairs.
Unstable operation under load, spontaneous reboots, or a complete failure to generate VCC_CORE . | Symptom | Check in Schematic | Common
A voltage divider (e.g., 1.2kΩ / 750Ω) from Vcore to the controller’s FB pin (Pin 10). If a resistor drifts, the CPU receives 1.9V instead of 1.25V, instantly burning the CPU.
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:
