There is no such thing as a world wide Dell warranty. IF the model you purchase is sold (and therefore supported) in Turkey, you can transfer a warranty, and IF you purchase the system with an onsite service upgrade. The basic 12 month warranty is Return to Depot. It cannot be transferred internationally.  And if the model you purchase is not sold in Turkey, you will find no warranty, service or support available there.  
I want to buy an Alienware from Dell Canada and use it in Turkey. I would like to learn, do I need to pay more to get world wide warranty? Or what should I do?  
Does Alienware offer a world wide warranty?