Why is my TV giving a black screen but am hearing sound

@jervanthomas first you need to verify that you have no image on all inputs. If it remains dark, unplug it and push the power button for about one minute, then plug it back in. See if that resets your TV.

If it remains dark, in a darkened room, use a flashlight and shine it at an angle against the screen, with the TV at a channel where you can hear the sound. See if you can make out shadows or shapes. If you do, then it is your backlight that has failed. If you do not see anything, unplug your set and remove the back. Then visually check the boards for any obvious damage like domed or leaking capacitors. Check all the wiring. Unplug the wires and plug them back in to make sure they are properly seated.

Since this is a Samsung TV, you can check the backlight easily. Unplug the power board, disconnect the main board from the power board. Connect the AC power to the power board. Your backlight should come on. You can verify this, by checking for the light through the numerous holes in the back off the panel.

Post some images of all of your boards with your question. Use this guide Adicionar imagens a uma pergunta já existente for that so we can see what you see. It is possible that this could be a power board issue or a T-con board issue.