Change boot order in bios when powering up computer will tell machine which drive to boot from
I personally would also change sata connector for drive to first sata plug on mobo normally sata0 just be aware that if you reinstalled to new drive with old drive still connected the boot info for windows (the little 100MB partition) may still be on old drive so to be safe have a recovery disk ready I case you need to do a startup repair or post a screenshot of your disk management if your not sure and we can advise