ok now that you know how to hook it up..
http://www.mp3car.com/vbulletin/faq-emporium/53523-faq-how-wire-opus-psu.html ..
your OPUS 150 may still not work... why? You're shorting a circuit!
How do you know if this may be your problem:
1) you double checked all your wiring
2) you made sure the power switch was in its correct polarity
3) you made sure your BIOS settings were correct
4) you pulled out some hair
5) after starting the ingnition the green LED on the OPUS will light up, signaling there is enough power, BUT the mobo doesnt turn on.. AND the fan on the OPUS doesnt turn on!
If this is true you most likely have a short circuit in your OPUS... To confirm that this is your problem take off the screws on your OPUS and remove the top casing with the fan still attached. Now, try turning on the ignition... If it works then your OPUS was suffering from a short circuit.
How to fix:
1) Check the coil right behind the 8 pin connector
2) You will find that it rubs against the cover of your OPUS, this is your short
3) To fix this, simply take some electrical tape and cover up the portion of the case that rubs against the coil.
That should do it!
Not the best pic but you get the idea: