The daughter board ain't useful at all. For what I've been reading comparing the other Asus that had such board, the P8Z77-I Deluxe, the difference between it and the Asrock Z77-E ITX are minimum. Also, this new ROG version not only comes with such daughter board, but also with YET ANOTHER daughter board for... a DAC? It makes absolutely no sense at all, and I have no idea why people are digging this board so much. It offers nothing interesting.
For starters, why would you want the best overclocking Z87 board... when you are going to put it into a mITX enclosure? The S3, prodigy and the like are only mITX because they say so, because volume wise they are MUCH bigger.
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