Unless he means the AM2 riser board for the Asrock Dual SATA 2 motherboards. In which case OCW has done a review and compared the results of the riser board versus a regular AM2 setup. Google that and check it out.
That's what I meant.
And I think it works for the 939Dual-VSTA, too.
It says here:
(Supports CPU upgrade from AMD Socket 939 CPU to Socket AM2 CPU through AM2CPU Board)