So, as I said above. I want a laptop (17" prefered) that can game. I prefer 1080 as well. It does not have to be new. I am looking for the lowest cost for effective gaming. I play mostly Planetside 2. I don't mind an older gaming laptop, but not so sure about them. I understand a GTX 1050 with a 1080 screen will game well. How about a GTX 670M or the older mobile GPUs?
I don't want something too old like a core 2 duo. I figure at least Sandy Bridge or newer.
There are so many used systems out there that you need to do your own search where you are located, or check eBay. You also need to list a budget. For a lower gaming system that won't have too many compromises you want about $700. Used prices can be all over the place. A 670M would be OK for older games but expect new ones to have issue and you will have no warranty on the system, it's a pretty old video card. The 9xxM or MX models would be much better to find.
The GTX 670m is rather weak nowadays. It is about equal to a 940m. The mx150 is the successor to the 940mx and it's performance is roughly halfway between the GTX 950m and GTX 960m. The GTX 1050 is about halfway between the GTX 965m and 970m; it is currently the weakest current generation nVidia GPU that is considered to be a "gaming" GPU.
The least expensive new 17.3" laptop with a GTX 1050 that I can find is the following Dell G3 laptop for $700. It has two reviews 4 stars and 1 star. It seems the bad review is result of Windows getting corrupted which does not necessarily mean there was an actual problem with the hardware itself.