Diesse should be about soon, and he will give you the correct description of what is most likely happening, but until then, it sounds like the thingy in the monitor that handles the high tension bit of the switching to put the display on your screen.
The computer is a Medion MultiMedia PC Mocro ATX tower, Intel Pentium III processor operating Windows 98. The monitor is a Medion 1772ie 17" flat square CRT colour monitor and the graphics is an AGP 3D graphic controller with 16 MB NVidia Riva TNT.
Hope this helps in your diagnosis.
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