The Zotac Zbox ID92 is not quite as small as the PI320 pico at 7.4" x 7.4" x 2" (188 x 188 x 51 mm) nor as inexpensive as it ships for $486 sans memory, storage and OS.  However with a 2.9GHz Core i5-4570T is significantly more powerful and the HD4600 GPU will allow you to enjoy some light gaming and to enjoy 4K content with an appropriate display.  With both SATA and mSATA the storage subsystem is more agile and also upgradeable as are the two SO-DIMM slots.   The Tech Report quite liked this device for media but suggest those intending to spend more time gaming spend an extra $100 on the Zbox EN760 with its GTX860M.

"In recent months, we've reviewed two Gigabyte mini-PCs with Haswell inside. In light of those experiences, we figured we'd take a look at one of Zotac's newest Zbox systems: a 7.4" x 7.4" x 2" machine with a 35W Haswell processor, room for dual storage devices, and generous connectivity."

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