Only a guess, but have you checked if the monitor's PSU has a main fuse in it? If this is blown then it would indicate a more serious issue than the PSU being at fault itself.

I've also read that the high pitched sound is a common fault, with 90% of the time being caused by the flyback (LOPT) getting shorted inside, causing current to pass trough the horizontal transistor, which will kill that also. So check the caps for bulges and cracks. Basically check all the capacitors.

If you can't get it to work, someone in Manchester is selling a working one on Amibay if it interests you. Sale is here.