Dell Latitude 3440 2 Beeps Problem

[cygron]

Model: Dell Latitude 3440
Board id: DL340-HSW MB 13221-1 Rev: A00

Laptop produce 2 beeps. RAM is ok (replace and test). And i think RAM Slot is also ok. Board have 2 RAM Slots. All coils have voltage expect PL5101. DRAMRST has only 0.12V. BIOS flashing can't solve the problem. Need help.

PL4503 - 3.3V
PL4101 - 5V
PL4902 - 1.35V
PL4801 - 1V
PL4701 - 1.7V
PL4401 - 17V
PL5101 - 0V

PU5102 pins -
Pin 1 - not stable ( 0.5, 1.3, 5.9 etc ... )
Pin 2, 4 - 0V
Pin 3 - 0.95V
Pin 5 - 2.87V
Pin 6 - 2.48V
Pin 7 - 3.3V
Pin 8 - 17.3V

PU4901 pins -
Pin 1, 3, 5 - 0.67V
Pin 2, 9, 13, 14 - 1.35V
Pin 6 - 1.8V
Pin 8 - 1.3V
Pin 11, 19 - 0V
Pin 12 - 5V
Pin 15 - 6.4V
Pin 16, 20 - 3.3V
Pin 17 - 4.9V
Pin 18 - 0.65V

[Sephir0th]

You need to understand why the Enable for PU5102 is not stable. DGPU_PWROK asserted will be one of the requirements for example.