loading driver pre-installation

Hi,

I hope someone can post a brief answer to this seemingly illogical problem.
It would really help a LOT. I've already looked in all the usual places for
an answer.

I've built a new system from scratch. It's done, and now as the Vista Basic
64 goes through the normal installation process, I get a message saying no
hard drives are recognized, even though they show up fine in BIOS. I have
both a brand new Seagate & WD sata drives.

I downloaded an .exe from the motherboard website (Gigabyte) that I'm
supposed to pre-execute, and then when windows looks for hardware, I press
F6. They don't provide a simple driver file for me to save on a floppy or
CD that I could access during installation.

How do I run an .exe on a system that doesn't have an OS running yet?

I don't even see a way to interrupt the bootup except to go into BIOS etc.

Is there a way to run the .exe to install the driver before I install
windows?
Or is there a way to extract a hard disk driver from the windows
installation CD?

Thank you for any help you can share. It would certainly make the world a
better place.

Richard