The power button on my Philips 17" 107S CRT Monitor is brokewn and I need to open the case to replace it. How do I open the case. Most monitors have 4 fixing screws holding the case together. 2 at the bottom and 2 on the sides hidden behind snap-off covers. My monitor does not have screws on the sides and appears to be internally fixed at the top. How do I separate the case at the top? There is no information in the owner's manual. Perhaps spomeone could tell me what the service manual says. Thanks