Motherboard repair - Power articles

Example 1. A PCI1600-F motherboard does not shine. First, carry out visual inspection and found that power control IC U24 (AIC1569) Table
Surface are traces of burning, welding, under U24, check the external circuit was no exception. U24 replacement after the board returned to normal. According to the user

To reflect the board of this problem is more widespread, AIC1569 purchase more problematic, I have found from the information can be HIP6004
It is a direct substitute, we try. Left is more than changing down AIC1569, quite miserable bar.
Example 2. 1 PT-694X-A1 motherboard does not shine. First, carry out visual inspection, no exception, after the examination of the CPU's
Vcore power supply was found to 0V, and the power switch gate no incentive signals. The board adopted the Power Supply Control IC U5
LM2637, which controls the power switch, check its incentive to use the oscilloscope pulse output pin without waveform, while the Vcc pin of the
Voltage is normal. Checking the external components of the U5 no problems found that it is broken, the replacement U5 later, the board returned to normal.
Example 3. Gigabyte motherboard does not shine, but even the power supply fan does not turn, the board has been the maintenance too. Check
The power switch does not breakdown, the chassis power supply PS-ON terminal and ground shorted to force the boot, the power is still not on the increase. Measurement
5VSB end and power up terminal (POWER ON) voltage is normal, and thus suspect that the power supply may short-circuit the load of a road, building
Into a power protection. In comparison with other BX motherboards, we found resistance +12 V group is abnormally low, it is estimated the problem arises from
This. Some checks and found U1 (HIP6004) 18-pin (VCC), 17 feet (LGATE) to ground-line resistance is small.after replacing hip6004 the motherboard working normal