You better grab a magnifying glass, as this is the smallest fully fetched Z87 motherboard you will ever see. Yep, the Z87I is made ... MSI Z87I Mini-ITX motherboard tested and review
ITX boards are rather interesting, makes me want to build as small PC as possible without any cards. By the way, Guru3D should add new Prime95 to download section. 25.11 is ancient and doesn't even support AVX instructions. New Prime95 is much more stressful.
Other than a little extra trouble cooling a mini ITX system as compared to a larger factor and the other points mentioned here, are there any downsides to these small boards? I was thinking of getting a board like this with a single graphics card to keep in a (ventilated) draw.
The only thing I can say: WOW! I will for sure make an mITX build with this.. For myself or for a customer.. That board looks really good. Also here's an Aida memory with 3770k@4.9Ghz and memory 2400mhz@11-12-11-24-CR1 timings.