Gigabyte G1.Assassin: No Beep Code

Hey tomshardware community! I've got a question for you and it's pretty obvious what it's going to be based on due to the thread topic!

I'm working on a buddies' computer, which when being turned, no longer displays anything on his monitor. So we did the routine check up, i.e. different cables, different monitors to no avail. I went through it, disconnected everything, and essentially rebuilt the PC w/o taking the mobo off of the cases' stand offs.

The interesting thing I noticed was that the 1-watt speaker was not producing a beep code at all, which is never a good sign! According to the G1.Assassin Gigabyte manual (http://download.gigabyte.us/FileList/Manual/mb_manual_g...), it doesn't have a meaning! I tried taking out the speaker and properly seating it in there again, and checking all the other little 1 pin connectors, and it's all seated nicely, but still no beep or display!

My conclusion was that there is a problem with either the motherboard's 3.0 PCI.E 16X slots, or the video cards went bad. Anyone else have any other conclusions or tips for me?

Specifications:
Gigabyte G1.Assasin
2 x Water cooled GTX 580
16gb of Kingston Hyper TX1
Intel Core i7 Sandbrige 2700K
1200W Coolermaster Silent Pro
2TB 7,200 RPM Seagate Barracuda
(there's also supposed to be a Adata S511, but it's currently uninstalled)

P.S. In case you're curious, I did redo all the custom water cooling for the GPUs as well. WHY U NO WORK!?  

Edit: Off of the HD3000 graphics, the computer runs. So, GPUs toasted or PSU is powering them inadequately?