Hi guys, long time since my last post.
I built a new box during the summer and included an ASUS p8z77-v motherboad, while almost everything seems to work fine I am having the following issue:

The ethernet interface seems to work only if restarting the machine. If it is turned off and I turn it on, I find that it won't connect to the wired network, however, if I restart it it works without trouble. Wireless network is detected without trouble regardless of being turned on or restarted.

I have also found that when going into the mobo settings, a IBA GE slot sometimes appears as a boot option and sometimes when starting the computer an "intel Boot agent" appears.

Is there something wrong with drivers or is it hardware malfunction? Any suggestions?

Just to give you guys some more information that might be of help, I have used crunchbang (as live cd) ubuntu server 12.04, xubuntu 12.04 and Arch linux images from the last couple of months. If I type dhcpcd eth0 (always did this in arch to activate ethernet, until I properly configured it in the appropriate file) a message appears telling me that interface eth0 is not available. I have been using 64 bit images and EFI