Make sure your new HDD is set as the first boot device in BIOS Setup. Then save changes & exit (F10).
To access BIOS Setup on an Acer you usually have to keep tapping the Delete key or the F2 key as soon as you power up (if Delete doesn't do it, power up again and try F2).
PS: I assume you have installed an operating system on the new hard drive? If you haven't your system can't boot from it anyway.