I see the topic is still open.
How to put full boot loader on a second Hard Drive.
This discussion is specific to the official release to the official release of Microsoft Windows 7. This may or may not apply to the trial versions of Windows 7.
The first step of course is to power down the computer completely and remove the first hard drive out of the system. Turn the power back on, go into the BIOS and make sure the drive that had been the second is now the only one in the system and it will be the default boot drive after the CD-ROM. Next, placed your Windows 7 DVD into your combo CD/DVD reader and reboot the system when you get the message to press any key and let the Windows 7 installer begin.
At this point Windows 7 installer should realize you already have Windows 7 is installed on the only hard drive in the system. It will then attempt to repair or recover that installation. If it is successful you will then have a complete boot loader on the second drive, which is now the only drive.
Unlike some versions of Linux, Windows 7 will allow the single drive to be either be the first or second in the physical hardware array. Logically Windows 7 sees the only drive as the boot drive.
Reboot the system at least two times to make sure it is working normally. Then power down and put back in your first drive and configure the BIOS to your preferences for the boot order.
The BIOS should have an alternate boot menu available to you. On some systems this is done by hitting F8 before the Windows loader starts. On others it might be the F12 key. See your documentation. With each hard drive having its own full boot loader, you should be able to boot either drive independently whether not the other is present.
This this procedure requires use of the installation DVD in order to make a repair on the boot sector of the drive of interest. Now if sing a USB device as a DVD emulation that should also work. However, I have not tested a DVD emulator with the Windows 7 installation DVD.
We hope this is of some help to you.
And by the way, there is some new information available about a trial version of Windows 7 that is available for some users.