Is this is just in windows or does it do it from the first screen? If the latter then you can do something like uninstall the drivers and run on the basic inbuilt graphics functionality. It will be slow for things like games and video but will work. If the latter then it is not good news, not that the other option was much better, and if you still have a warranty then I would consider using that. I am not entirely familiar with French warranty law, assuming you flag is accurate, but many European countries will have decent consumer protection -- the UK has one called the sale of goods act which means items technically have a warranty for their reasonable life (so 5 years for a laptop is good) and you can probably get something done there.
Otherwise yeah it looks like the graphics chip is on the way out. If you have a dual graphics chip laptop then go to the other, if you know someone that can redo BGA (it is a fairly high end and less common electronics manufacture/repair technique so maybe not) then maybe consider that and finally there are options for many newer laptops to drop the wireless card and put a desktop graphics card in there instead (the wifi usually goes over a version of PCIe so you buy a 40 Euro adapter and plug it in that --
http://www.banggood.com/EXP-GDC-Laptop-External-PCI-E-Graphics-Card-p-934367.html would be an example of one such device).
