Same power; smaller package.
For testing the Zotac A75-ITX WiFi I have used an AMD A8-3850 APU, 2x2GB Kingston DDR3-2133MHz RAM (running at 1333MHz) and WD VelociRaptor 300GB HDD. For comparisons I’ve used the slightly bigger Gigabyte A75M-UD2H.
On an average, the Zotac A75-ITX is 4% slower than the Gigabyte A75M-UD2H, while also being 27% more expensive. That said, the Zotac board does have 6x USB 3.0 ports compared to two on the Gigabyte, not to mention dual-LAN. Is that worth an extra $30, though? Well, that depends on your HTPC case then. If you want a system with the smallest possible footprint, the Zotac A75-ITX, with all its bells & whistles is unbeatable, I just wish the price would be lower.