Drives not detected - 1tb SATA - as shipped - Proliant Microserver Gen8

[pbasics]

Setting up a new micro gen8 which shipped with 4x 1TB sata drives.  Before first boot, I replaced 2 of the drives with crucial mx300 SSDs 525gb.  I went through inteligent provisioning and only the SSDs showed up in the smart array configuration.  I put them into an array, and installed win 2012 r2. 

Server boots fine into win2012, except the other two drives are never recognized.

I swapped the SSDs and HDDs slots and still boots, but only finds the SSDs.

I replaced all 4 HDDs and attempted to configure, but now the array controled shows error (!) and no physical drives.

Swapped back to SSDs and boots fine, but does not find the HDDs.

Newbie to servers/arrays - but far from the same on PCs - thanks!