As a matter of fact, the DH61AG does support mSATA, at a 3.0 Gb/s speed. For more information, please refer to the following websites:
Unfortunately, not all mSATA SSD in the existing market is supported by DH61AG...
Recently, I just got this MB from eBay & try to install a KingSpec's 120GB mSATA SSD (http://www.kingspec.com/en/product_xx5.html) but failed. The BIOS simply does not recognise it
And I heard from other forum that users reported their OCZ mSATA SSD did not work as well...
So, Intel, any chance to fix it in the future BIOS update, please?