After the switch of the graphicscard last week, the problems with my laptop persisted. That meant that the friendly technician went out of the door and came back a day later with a new mainboard for my computer. After exchanging that - the weirdness on the screen was gone - finally.
So I’m left with a 80% new computer: The case, HD, DVD and battery are old, the rest is new ;-) I think that Dell is working on their support processes to minimize the occurence of another case of changing three components before their computer starts working again - a call from their service center an hour after the technician left, leads me to believe that.
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