Everything seems to be hooked up correctly--I've tried connecting vga and hdmi to multiple monitors directly to the motherboard and also tried booting to bios. I have yet to find anything specific about Dr DeBug Code 15, but have found that it's likely a problem related to memory. I'm using Corsair Vengeance 8GB (2 x 4GB) and have tried re-installing multiple times, and using only one of two sticks of ram. The next thing to do is probably to re-install the CPU, which sounds awfully terrifying, so if there's anything I should try before this please let me know.