X99 based systems do not come cheap, with some boards costing well over $300 and very few under $200 the X99P-SLI could be considered mid-range.  The board doesn't skimp on a lot at this price either, an M.2 slot, a pair of USB 3.1 ports, OP-AMP based onboard sound, a conveniently placed header for USB 3.0 on your front panel and yes, it does have a single SEx port.  Hardware Canucks breaks down how the PCIe slots are shared and many other of the boards features in their review which you should check out, the board was determined to be a Dam Good Value.

"The X99 platform may not be known for affordability but Gigabyte's new X99P-SLI aims to change that opinion with USB 3.1, M.2, great overclocking, quad GPU support and more for less than $250."

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