Hi guys,

I am new to linux and I've been trying for some time now to use me laptop (Dell inspiration 1525) with my 19" display extending the one on the laptop. I finaly did it and want to post this in order others like me to be able to do it faster. I tried like 100 different things and nothing worked. I edited the xorg.conf file 1000 time and the line that did the work FINALY was:
SubSection "Display"
Virtual 2560 1024
EndSubSection
Just put that in the "Screen" section and you're done. You can edit the size in order to fit what sizes are your screens. And to position them i use xradr and i tool for it grandr. You can change the positioning of your displays there easy.

I hope that this save's someone some time.