Hi jamrockz,
Welcome to forum,
What is your Revision of your motherboard?
See here, he have many revisions...
http://www.gigabyte.com/products/product-page.aspx?pid=4329#ovGA-Z77M-D3H (rev. 1.0)
GA-Z77M-D3H (rev. 1.1)
See page 3 in your manual, for how to check...
Otherwise...
Before insall friend's Cpu... have you check if a pins are okay, not bent, altered...
or the socket... on friend's computer...
Before this ''situation explain by you'''....
Have you used all memory on the motherboard, without problems?
Have you tried on other motherboard?
Please describe with more details, your hardware...
PSU, SSD, hard disk, graphics card, CPU, ....