Hey bettz I don't think you have the wires in question connected correctly. The connector with red and black wires labelled M/B PWR GND has to connect to the mobo PWRSW header. The arrow in the picture points to the PWRSW header where you already have something connected. I assume that the black & white wires are from the cases on/off switch. The +5V/GND pins are part of the 4 pin header for the speaker so you shouldn't be connected there. The red & black wires connect to the PWRSW header on the mobo and the black & white wires get attached to a header on the back of the LCD display board. Should look something like this. If this doesn't help with powering on, using the mobo & case manuals I would re-check all of the connections you made hooking things up during the build. Also have you tried your PSU in your Dad's sytem? While not the ideal solution you can get away with using a 2 molex to 8 pin adapter as long as you connect the molex connectors to different 12V rails on the PSU. You should really be using a newer PSU that has an 8 pin EPS +12V connector.