|Note that you can read your temps in your BIOS as well as your input voltages. Post these when you first turn it on and after sitting on for 10 minutes.|
Has this system ever worked properly? If it is a custom built system, especially a new one, pull it all down and bench test it.
Use only MB, CPU, one stick of RAM, onboard graphics or one video card, at first, then add one component at a time. Add the second graphics card last, after Windows and drivers are all set up.
You have to be a little bit crazy to keep you from going insane.