Should I buy the ASUS Z170 Deluxe or GIGABYTE Z170X-Gaming G1 motherboard?
Hey there Ahmed,
To be totally truthful, either motherboard is going to be great. Both of them are based on the same chipset and will have virtually the same feature set (M.2 support for SSDs, multiple PCIe ports, and so much more).
Both of the motherboards are super enthusiast high-end boards that will let you overclock whichever processor you're going to use, and I presume you'll be using a Core i7-6700K, to its maximum potential. Both boards also look great, with similar styling - but if it was down to physical appearance, I think the GIGABYTE Z170X-Gaming G1 looks better.
It really comes down to your brand loyalty. I love both brands and have two high-end systems in my office built on a motherboard from both GIGABYTE and ASUS and I haven't had an issue with either. You can be confident in knowing that any choice you make you will love it.