Technical Support lenovo b40-70

[Kanini Technology]

la-b092p
power on display come then suddenly off
3v and 5v ok
without ram to power switch voltage stable to 3v but with ram to power switch voltage going down
need help bios and ec programmed
io also changed

 

[Ahmad Safari]

Hello
You should find all the voltages on the motherboard from the schematic and measure their resistance to the ground.Also, sometimes the voltage drops, which can be detected by measuring the voltage.