2 hdds, 1st OSX, 2nd Windows, No Bootable Device, remove 1st windows boot

desired scanario:



2 hdd:



1st - ssd - OSX (Mavericks) (has two internal partitions - MacOSX & OSX_Data)

2nd hdd - 500gb hdd in optical bay.



want to install windows 7 on second hdd, via bootable usb with installer



steps taken :



bootcamp > new windows > pick 2nd drive, (single partition of 500gb) > restart



> windows could not install, error



> open macbook, unplug primary ssd (Mac OSX)



> restart > windows installs on 2nd ssd



now.....



if primary is unplugged, macbok will boot in to windows

but

if primary ssd is pluged in, after holding alt (option) key, MacOSX and Windows come, but only MacOSX works.. Windows gives error of - No Bootable Device....





any ideas?



p.s. macbook pro 15" 2012

mavericks