Motherboard Recommendation for HD Native or HDX PT11

What PC Motherboards are most compatible with the new Avid HDX & HD Native PCIE cards? Are any Asus motherboards certified compatible? Where would I find info on motherboard compatibility for HDX?

I need 3 PCIE slots, one for my UAD Octo, one for the HD Native card(upgradable to HDX), & one for whatever may come in the future.



Are PCIE slots all the same size? If not, what size will the Avid HD Native card, HDX card & UAD Octo card fit in? Are those all the same size cards?



I plan on either an i7 2600 or i7 4700 for this computer. Will either one of those processors work? Is there info on processor compatibility?

Also, will Windows 7 Professional Plus work with PTHD Native 11? Any info about operating system compatibility?



Thanks for any information you can share. I'm ready to purchase HD Native, and will be able to upgrade to HDX in a few months...Of course I need a computer that will work with these cards and PT HD11 first.

Thanks!