At least not anymore, thanks to Intel's Thin Mini-ITX platform, which it debuted roughly a year ago at Computex.

ENGADGET: Intel's Thin Mini-ITX platform gets stuffed inside a monitor

In addition, it conforms to Intel Thin Mini-ITX standards, meaning even the motherboard is upgradeable, a first in the PC industry.

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The main board is the same footprint as Mini-ITX (that's a 6.7-inch square), but it calls for a much shallower construction -- with horizontally stacked RAM and a shorter port cluster to keep the whole thing under an inch tall.

ENGADGET: Intel's Thin Mini-ITX platform gets stuffed inside a monitor

It's not hard to imagine why people would want a motherboard as small as VIA's PX10000: its low power requirements (the guys at Mini-ITX.com couldn't get it to draw more than 16 Watts under full load) and miniscule size (less than 4 inches long) make it perfect for really small enclosures.

ENGADGET: VIA EPIA PX10000 Pico-ITX motherboard gets reviewed

Carrying a 4 x 4-inch form factor between a Raspberry Pi and mini-ITX board, it'll be equipped with a Core i3 Ivy Bridge processor, HD 4000 graphics, two SoDIMM sockets, an mSATA slot for an SSD drive, three USB ports, one HDMI port and a mini-PCI slot for wireless connectivity.

ENGADGET: Intel's Core i3 NUC mini-boards set to hit market in October, power up hobbyists and OEMs