Alienware 15 R3 SSD 3 seems to be extremely hard to remove, don't know why this came installed when I bought it it also has windows on it but that shouldn't matter. :
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Alienware 15 R3 - i7-6700HQ · NVIDIA GeForce GTX 1060 · 15.6”, Full HD (1920 x 1080), TN · 256GB SSD · 1000GB HDD · 16GB DDR4 · Windows 10 Home | LaptopMedia.com
New Alienware 15 R3 CPU Graphics Cooling Fan/Heatsink K1W4D
Best Buy: Alienware m15 R3 15.6" Gaming Laptop Intel Core i7 16GB Memory NVIDIA GeForce RTX 2070 SUPER 512GB Solid State Drive Dark Side Of The Moon AWM15-7593BLK-PUS
Alienware 15 R3 Review - Gaming Laptop Reviews by MobileTechReview
How to boot from new SSD upgrade for Alienware 15 R3? : r/Alienware