04-23-2018 07:33 PM
ThinkPad E550 Type 20DF-004DUS. Thinkpad boots but sceen is black. Sometimes if USB drives or USB connections are removed, the sceen comes on. Sometimes, connecting another screen via VGA cable... the extenal screen comes on. But not always. Here lately, neither the laptop screen nor an external screen comes on. Took it into a shop and they replaced the motherboard... but that did not work so they put the old motherboard back in. They couldn't get either the laptop screen or an external screen to light up with with either motherboard. They tested the laptop screen out of the unit and it worked as expected.
Sometimes I get a screen and sometimes I don't.
What has me confused is exactly why these problems are happening. Could the cable between the laptop screen and the motherboard be bad? And, if so, could THAT cause the external moniter to be black as well?
Have any of you experienced this?