Black screen at the boot after install nvidia proprietary driver Arch Linux

Today I have installed Arch Linux on my desktop PC and I have occurred in a fault. After the install of Nvidia driver package I have rebooted the system and after the choose of OS in grub the screen is became black.
If I press Ctrl-Alt-Canc the system reboot. I have realized immediately that the error is caused by a conflict of some graphics modules.

I have in my PC an Intel I5 2500k Sandy Bridge(with the integrated graphics card) and a Nvidia GeForce 560.

After a search on the forum of Arch Linux I have known that the system choose the Intel graphics card at boot instead of the Nvidia graphics card, thus load the module for Intel card instead of Nvidia card.

For resolve the problem I have created the file /etc/modprobe.d/blacklist.conf and I have put in this 2 rows:

install i915 /bin/false
install intel_agp /bin/false

With this file, at the boot time, this 2 modules aren't loaded and the system work well with the proprietary Nvidia graphics driver.