monitor tech

hey does anyone know what a set and transistors are for in a monitor..awhile back i posted some monitor problems with my sony vaio display HDM-A200L ..it was refurbished and it worked for awhile but when i changed cards from a pci to agp it went whack and the thing wouldnt display nuthin..i used a spare monitor i had and the cards woked fine so it was my monitor..i took it in for repair about a month ago and the fools say that they are still looking for parts( the set and transistor) how hard is it really to get these parts? please help i miss my monitor...