Actually is windows 10 but they're pretty similar

Sorry for replying so late, haven't been hanging out on blendswap in a while. I basically just made a shader for the screen when it's turned off (use a glossy shader that's dark-grey and add a little bit of roughness (I just realised I, for some reason, mixed the gloss with a diffuse shader)), and then, in the same material slot, added an emission shader and adjusted the emission value to my liking. Then I plugged both screen-materials into a "mix-shader" node, and made a node group. I plugged a texture into the emission colour and made sure I could adjust the mix-shader node without having to go into the group. Summed up, I made two materials for the screen, one when it's turned off and one when it's turned on, and plugged them into a mix-shader node, so that I could choose if I wanted it turned on or off without having to fiddle around with the nodes too much.