Скачать или смотреть How to replace LCD Screen on Dell Precision 7740

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For the replacement process we’ll need the following tools:
a Plastic Pick
and a Phillips Screwdriver

To begin turn off the laptop and disconnect the power cord.

Using plastic pick pry off the bezel on the inner edge while unsnapping
the tabs with other hand. Start from the side and go along the perimeter.
Put the bezel aside.

Using Phillips screwdriver remove four screws holding the screen in the corners.
Place the screen on the keyboard. This is a rare case when video connector
is secured with TWO layers of tape. Peel off the first silver tape. Then peel off
the clear tape. Peel off a blue foamy and keep it for future use.
Open the connector’s bracket. Disconnect the video cable. Discard the old screen.

Place the new screen on the keyboard. Reconnect the video cable. Close the
connector’s bracket. Reapply the blue foamy. Secure the connector with clear tape
then with silver tape.

CAUTION! It is very important not to force any connectors. Also make sure not
to twist or slant the connector when plugging it in.

Lift the screen up and lean it on the back cover. Test the new screen.
The screen is working and we can finish reinstallation process.

Replace 4 Phillips screws holding the screen in the corners.

Make sure that cables are in the right position and replace the bezel.
Start from the bottom and then go along the perimeter snapping tabs
back in place. Use one hand to support the back cover while snapping
the tabs along the bottom edge.

Turn the laptop on, and we are done!