I have ordered a new monitor, since the old one detoriates even further. It seems to be the most reasonable hardware component to check first, obviously. I hope it is like that indeed, and the money is not wasted (shop said for giving it a full diagnosis they would request 150 bucks, well that IS the money for a new monitor). If the problem remains with the new one, than I have wasted money, and the gfx board needs to follow. Hope it aint so.
Monitor is older than the system, btw, around 4-5 years.
Old CRT TV's used to hold 12-20 years, and more.