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The System76 Oryx Pro is one of the most powerful and customizable laptops in the market. It comes with Linux pre-installed but you can install Windows and dual-boot if you want to use it for gaming or for Windows development.
SpecsUpdate
Pros
Pro Amazing overall performance
The default 6th generation i7 Processor coupled with the 16GB of RAM (even better with the versions with 32GB and 64GB) make for an absolutely amazing machine. It has a dedicated SSD for the OS only which massively increases startup time and for anything else you can choose up to two SSDs or HDDs of varying sizes. The Oryx Pro is perfectly capable of doing some heavy-lifting including 4K video editing and gaming at highest settings without a hitch.
Pro Good for gaming
The Oryx Pro is probably the best laptop with Linux support out of the box that is great for gaming as well. This is mostly because of the NVIDIA graphics cards. It comes by default with the GTX 1060 but for $289 more, you can add a GTX 1070 instead. The default 8GB of RAM is good for gaming but the 16GB RAM is ideal.
Pro Very customizable
Before buying the System76 Oryx Pro from the System76 website, you get to customize almost every aspect of the laptop as far as specs go. The price depends on what you choose to put inside your laptop and prices vary from $1475 for the basic version to $7000 for a laptop with a 17.3" Matte IPS Display, a GTX 1070, 6th Gen i7 CPU, 64GB RAM, and two SSDs of 5TB and 4TB respectively.
Pro Great Linux support
All System76 laptops come with Linux out of the box. The Oryx Pro comes with either Ubuntu 16.04 LTS or Ubuntu 16.10. But that does not mean that other Linux distributions are not supported, quite the contrary. Most Linux distros should work without any major problems with the Oryx pro and most (if not all) drivers are available.
Cons
Con Customer service could be much better
System76's technical support is pretty bad. When there's a problem that should be solved by them, they usually resort to sending replacement parts instead or blaming third-parties (even if those third-parties are not at fault) of something that they should be fixing.
Con Very heavy and bulky
Weighing at 5.5lbs for the 15.6" version it's relatively heavy and it's one inch thicker than the XPS 13. But the extra space is not put to waste, considering how it has an Ethernet port, SD card slot, 2 Mini DisplayPrts, HDMI port, 2 USB 3.1 Type-C ports, 3 USB 3.0 Type-A ports and headphone and mic jacks. The GTX 1070 version also includes a headphone amplifier. However, the power brick that comes with the charger is ridiculously large at 2lbs which understandably adds to the weight of the laptop since most of the time you have to carry both with you.