Mobile graphics cards are weaker than their desktop namesakes; might have less of everything. It used to be a brutal 50% computing power compared to the non-M variant but I heard it is not that bad anymore, still weaker.

I agree that if you are buying a gaming laptop, you should get at least a 1060 (if going for nVidia).

Do not buy a brand that does not let you update your graphics card drivers from nVidia (or AMD if that would be the case).

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(As a side note, I still do not get those who buy gaming laptops but that was not really the topic here. Maybe very tight on space, maybe loves LAN parties.)

I think that by now you have a consensus. Better an I7, with a 1060. And don't bother about 7xxx or 6xxx.

Still, you may want to check how easy it is to replace the battery , the ram and the HDD. Some modern laptops can be a major nnoyance by having an integrated, non replaceable battery or make it very difficult to swap the HDD. I had one like that for 18 months .... to throw it to garbage and replace it by a second hand elitebook

I would ditch the 1tb HDD, go for a 250gb or 500gb SSD - this alone is the biggest improvement to PC's I have seen. External HDD's are fine, small ones (I have a WD 4tb which is a small one, size of credit card, but much thicker) you can get in large capacity, with USB 3.x which is plenty fast. Then on your main machine only keep software you actually need/use, to often people just install everything and then complain they run out of space.

A 17" laptop usually has two hdd bays or a hdd and an M2 ssd slot.

Buy a 15.6" not a 17"

A 17" is big and heavy, you may as well buy a desktop instead.

My course tutor has a Lenovo Yoga and that packs an I-7 as well as an SSD drive. Make sure you get at least a 256GB SSD drive. You will use it up fast!

I have an SSD on my new ACER laptop, which has a measly AMD A-4 processor. The SSD prevents applications from suffering fatal crashes. It always recovers because the SSD is fast.

If thats the case, then wonderful, main SSD with things installed on, the other as storage. That way you only need 1 or 2 external drives for backup :o)

Whoa, a lot of answers (and questions), thanks a lot :-) I'll post in few hours with more details and answers to your further questions!

I prefer for example 17" more. First the cooling is better in 17" ones (more space for heatsinks, air vents etc.), more space for extra hdd/ssd, usually 4 RAM slots. Also a real numeric keyboard. And did I mention the bigger screen?

All of that. And the airlines charge a mint for taking a desktop, screen, and keyboard onto the plane.

The only significant downside I've encountered is finding a backpack that will fit a 17" gaming laptop.

Anyway, size is a matter for the OP to decide.

I'll never understand why people want to game on laptops

Which is another way of saying, "Some of us travel and would like to take our hobby with us". If one has the luxury of playing PC games in the exact same place every single time, then a desktop is a fine solution. If not, then a desktop is a lousy solution.

For me it is the portability. I may quite often move my gaming laptop around the house (esp. if I want to connect it to the TV in the living room), and being able to take it even to e.g. the summer cottage or Thailand (for the rainy days, you knows) doesn't hurt either.

A desktop PC feels like it is bolted to the ground, you won't normally move it around, even inside your home.

It is not only "LAN parties". Just playing e.g. Team Fortress 2 online with your friend in the same team is better when you can share a desk with two laptops on it. Then you can communicate without using a microphone, and it makes it much easier to synchronize your actions when you can see what is happening on the other person's screen.

A real life case, I have built a sentry gun behind our base front door in TF2 (the Turbine map), and then I ask a friend to open the door briefly so that I can teleport the sentry gun to the other side of the area. If someone was keeping the door open for too long, enemies would easily destroy the sentry gun from a distance, so the door much be opened exactly when I say it. It is also much easier to explain to him what I want to be done and where, when I can show it on my screen briefly.

Moving another desktop into the same room/desk just feels like an overkill for playing TF2 effectively together.

That fine and all. Some people don't understand why people want to play on PCs ("consoles are designed for gaming you knows! PCs are for running WordStar."), and some people don't understand why anyone would play games at all, since they are just for kids.

Totally agree here, I like taking it whereever I want, be it in house and garden at home, or to friends or to holidays.

Just because oneself doesn`t have a use for it doesn`t mean others wont, too.

And to add, there are quite some portable 17" laptops out. Mine is just 3kg and easily fits in both of my backpacks together with other things ;)

I don't know if they are the correct terms, but I consider my heavy 17" laptop as "portable". Ie. it is quite easy to pack and move around to another place in order to use there, but I wouldn't try to use it on e.g. a crowded bus.

Mobile phones and tablets I consider "mobile", ie. they can be used also on the road, like in that crowded bus.

Yupp. I have a Tragus backpack I've bought in 2009, and they don't seem to make this model anymore so I'm hanging on to it even though I've changed two laptops since then.