Tyan AMD Board S8225WAGM4NRF
I've passthrough working on this Tyan AMD board with ESXI 5http://tyan.com/product_SKU_spec.aspx?ProductType=MB&pid=687&SKU=600000213
I specifically have the S8225WAGM4NRF, but I would imagine the entire family would work.
Make sure you update the bios, or enabling IOMMU will prevent the board from POST'ing
I'm running bios v1.01a beta
I'm passing through two of the onboard nics, the onboard LSI SAS2008, an Intel sasuc8i, and a fax modem