Great news. I just found this Eyefinity FAQ page which confirms your comments: http://www.amd.com/us/products/technologies/amd-eyefinity-technology/how-to/Pages/faqs.aspx#how-many-monitors
So, since the mini DP isn't required, do I need an active adapter for the HDMI to DVI? I'm thinking not (not even sure it exists). I'm thinking that a neater solution would be to get a HDMI to DVI cable (rather than an adapter). I need a slightly longer cable anyway. Thoughts?
Many thanks for your help!