Installing OS with 2 drives

[TunnelCat]

I'm working on my first build, so I have never done this before, and info is kind of scarce on this.
I want to install Windows 10 from a flash drive to a computer with an SSD and an HDD. First off, how do I install from a flash drive, and secondly, how do I specify which drive to put the OS on?
- Thanks!

 

[CountMike]

Disconnect second drive, boot from USB flash drive and install windows. After finishing, ad second drive and format it if necessary.

 

[Boogieman_WD]

Hey there, TunnelCat.

First and foremost, you should set your SATA mode to AHCI. You can do that by going to your BIOS/UEFI and finding the option I'm talking about. Sometimes it's set to IDE so if it's not AHCI, just change it and then click save & exit.

When doing a fresh install of Windows, it's always recommended to have all secondary drives disconnected from the motherboard during the installation process. This is necessary as sometimes, some of the system files and/or partition might be written on one of the secondary drives and thus lead to future problems.

As for your question on how to install Windows via a USB flash drive, you can check out this link: http://www.tenforums.com/tutorials/2376-usb-flash-drive-create-install-windows-10-a.html, this will show you how to properly create a bootable flash drive with Windows 10. The only thing you need to do when this has been done is to go to your BIOS/UEFI and set the flash drive as the first booting option so that when you save & exit the BIOS and the computer restarts, it will boot to the Windows installation and you can continue from there the same way as if you were installing Windows via a DVD.

Here's another useful tutorial: http://www.howtogeek.com/197559/how-to-install-windows-10-on-your-pc/.

Hope that helps.
Boogieman_WD