Typically features AMD Beema/Mullins processors (e.g., AMD A6-7310 or A8-7410) soldered to the board. Super I/O (EC):
Verify 3.3V on the power button and the BIOS chip (Pin 8). La-c781p Schematic
The main power rail (VIN). It enters through the DC jack and passes through two entry MOSFETs controlled by the charging IC. +3VALW / +5VALW: "Always-on" rails. On this board, the RT8243 (PU2) often acts as the PWM controller for these voltages. Typically features AMD Beema/Mullins processors (e
Backlight doesn’t come on, external monitor works. It enters through the DC jack and passes
You have a dead laptop. 19V is entering the board, but the fan doesn't spin. A generic multimeter check shows the 3.3V is present. Most people stop here and assume the BIOS is corrupt.
: This board requires 19V to enter through the DC jack. Issues are often found in the initial MOSFETs or the charging IC. Voltage Rails