I have a mid 2012 (which ever preceeds the late 2012) 21" iMac. I have installed an aftermarket SSD and a 2TB HDD. iMac works fine. I am trying to install win7 via boot camp. I have downloaded windows support software to a USB drive and proceeded to install win7 via disc. It partions the HDD (or at least tries) and then the iMac re-boots on its own to a white screen. Then after about a miniute the screen goes black and states somethng like "no bootable disc available". This also happened when i tried it on the SSD. I am running the latest version of Mavericks.