The MSI GS30 Shadow is a high powered laptop with the first external GPU that you can actually buy.  The GamingDock is indeed rather unattractive and hefty on the outside but it is what is on the inside that counts, a full GTX 980 with its own dedicated PSU.  The external connection is a rear mounted PCIe slot which allows the 980 to run at the speeds you would expect it it were inside a desktop PC.  The laptop itself has a Haswell i7-4870HQ, 16GB of DDR3-1600 and pair of Kingston 256GB M.2 SSDs in RAID 0, with the only internal graphics being the Iris Pro 5200 on the CPU.  Kitguru has posted a review here, though it would be interesting another review featuring a head to head competition with the GTX980M.

"When we previewed the MSI GS30 Shadow and GamingDock at the end of 2014 we were blown away by the combination of Core i7-4870HQ CPU in the laptop and the desktop GTX 980 graphics card in the GamingDock. The concept of using an external dock to add proper gaming graphics to a thin and light laptop worked superbly well and we could hardly wait for the official release of the final package of hardware."

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