Considering hardware for a gaming laptop. Not building my own, but found a great deal on a machine from last season still sporting a 4720HQ processor.Comparing benchmarks between the Haswell 4720HQ and the Skylake 6700HQ seems to suggest they're roughly comparable. The 6700 is, on average, about 5% better but some sites, such as cpuboss, actually suggest the older chip is marginally faster. There are lots of benchmarks and I'm not sure which to trust as regards a machine intended primarily for gaming, but from speed alone the 6700 doesn't appear to be worthwhile.However, speed isn't the only improvement in Haswell vs Skylake. Most of the others don't interest me. Better integrated graphics aren't much use in a machine with a dedicated GPU. The support for DDR4 isn't a big deal in a laptop where I'm unlikely to be upgrading the default RAM. The effeciency gains aren't helpful since I spend most of my time plugging in to a power socket.The differences in connectivity though, could be a big deal, and that's support for Thunderbolt and USB 3.1.About a year ago there was a big explosion in interest about Thunderbolt, partly because it offered the possibility of running desktop-grade GPUs as an external plug-in to laptops and all kinds of other cool stuff. Right now, I can't ascertain whether this has lead to any tangible use cases or is likely to. I'm not even entirely sure, to be honest, whether you can even buy non-Apple laptops with Thunderbolt ports, or how to find them (it seems to be referred to as USB Type-C in some places).So, is it realistic to go looking for a Skylake laptop with Thunderbolt, with a view to plugging in some monstrous desktop GPU, or some other reason (are the benchmarks lying)? Or should I stick with Haswell for now? 
Intel i7 4720HQ vs 6700HQ - worth it for Thunderbolt on gaming laptop?
laptop;gaming;processor;thunderbolt
High spec Haswells and Broadwells are going for absolute bargains right now and are excellent machines for most people that want very good gaming with normal work/social use cases. But if you primarily want to game on your laptop and if you don't want to wait and can find the 6700HQ (or something else) with something like a GTX 970M and a Thunderbolt 3 port (preferably more), then go for it. That should last you 2 years by which time there'll be much more external desktop GPUs to upgrade to via Thunderbolt 3. About a year ago there was a big explosion in interest about  Thunderbolt, partly because it offered the possibility of running  desktop-grade GPUs as an external plug-in to laptops and all kinds of  other cool stuff. Right now, I can't ascertain whether this has lead  to any tangible use cases or is likely to.To give an example (for non-hardcore gamers), Acer will be releasing a dock which features an NVIDIA GeForce GTX 960M graphics card, two DisplayPorts, a HDMI port, three Type A USB 3.0 ports, a headphone jack and an Ethernet port. Expected to be about 300, likely to be tied to Acer laptops.For serious desktop graphics cards, a number of enclosures are out now or just around the corner that take a full PCI-E x16 slotted card. Thunderbolt 3.0 doesn't nearly have the same bandwidth as PCI-E x16 and this does lead to a performance hit compared to a desktop (Asus say 1-5% fps hit for theirs); but a bit of perspective: you're running a desktop graphics card on your laptop :-O.There's the Asus ROG XG Station, as in a YouTube link above, tied to Acer laptops. Likely to be GPU manufacturer agnostic.Razer have Core, which is a docking station designed to enhance their ultrabook grade Blade Stealth, but is GPU and PC manufacturer agnostic. From what I gather, hot swap drivers drivers are built into the Core and load on the fly, unlike the other offerings where you'll have to power of your device to disconnect the external GPU. It has a built-in 500W power supply (supports a 350W GPU), four USB 3.0 ports and Ethernet port. Already shipping in the US for $500 (without a GPU), $400 with a Blade Stealth ($1000 starting). Expected to ship in April for Europe. This is the one I'm really excited about :-D.AMD are working on XConnect (with Razer), intended to be at least PC manufacturer agnostic.So if you get a Skylake gaming machine with Thunderbolt 3 soon, which typically last for 2 years, by then there'll be plenty more GPU and PC manufacturer agnostic enclosures around. If you go Haswell, although much cheaper now, you'll have to replace the whole machine at upgrade time.I'm not even entirely sure, to be honest, whether you can even buy  non-Apple laptops with Thunderbolt portsThunderbolt 3 is no pricey passing technology like Thunderbolt 1 & 2 before it. Nor should it ever be thought of as an Apple feature like Thunderbolt 1 & 2. Major manufactures have already released laptops with Thunderbolt 3 for their higher priced offerings and only more will follow suit. Here are only some examples.