The 8400 is DX10, though woefully underpowered for dx10,
shame you've ordered already as well this is quite a steal!
http://www.microdirect.co.uk/(17242)...56MB-PCIE.aspx
It is the cut down 'pro' version (3/4 of a XT) but its still 3x what an X1600 series (7600 rival)