There are *many* boards that support more than 2 USB 3.0 ports. In fact (at least in the 7 Series motherboards (for 2nd and 3rd generation Intel Core processors)), most have at least two USB 3.0 ports on the back panel and cable-up support for two USB 3.0 ports on the front panel.
Another way to find a motherboard that suits your need would be doing the following.
1. Find the model of the processor to be used here: http://ark.intel.com/ ARK | Your Source for Intel® Product Specifications
2. Look for compatible products on the left side of the website.
3. Click on "Find Compatible Desktop Boards
Then you would be prompted with a list of motherboards that are compatible with your CPU, in the specifications page (http://ark.intel.com/ ARK) for each Intel® board, you will be able to find the amount of USB 3.0 ports available.
I am positive that this information would assist your inquiry, if additional support is required, feel free to contact us back.
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