choose between windows 7 and Linux without bios change

And are you installing each OS with the other drive unplugged and making no changes to the bios during the whole procedure ?

Sorry that doesn't make a whole lot of sense to me :/

Removing the hdd with the first install and then installing the second os on the other hdd will insure both installs have their own boot loader.

michelvai said:

I have installed windows as an OS and the Linux too.

That does not answer my question in reply #11

He must have unplugged the drive with the first OS when installing the second OS. Else he would have a double boot now. But it is pretty neat as is. Switching the OS with the BIOS is not your worst choice. 2 independent OS installations have their advantages - e.g. when you want to uninstall or change one of them.

That`s true, but why does he have to go into the bios ?

He should be able to do it with the boot menu, but he can`t

With the boot menue is another way. For that you need both systems in the bootmgr. But if you installed the 2 systems independently, then you need to go via the BIOS.

If F8 does not work

Force Windows 7, 8, or 10 to Boot Into Safe Mode Without Using the F8 Key

if you can get there

If F8 is not the magic key for boot options then possibly F12 is :/
One of my systems is even F10
One is F12
One is F8
Very annoying to keep track of