hmm
17x17x8 does NOT turn into a 19" LCD
so you are right, something is fishy here

sqrt(17^2 + 17^2) = 24
for diagnal measurement
thats really strange...
or does are there 5 inches of diagnal border plastic we didnt take in account of?
perhaps thats it

24-5 = 19

but wait....
5 inches of plastic?

that sounds like a lot even for diagnal measuremeants for the corners...
hmm....

let us all investigate into this