I'm working with a Sony VAIO PCV-7741 computer. I think something maybe wrong with the mobo. Well, the power cable is plugged into the stock PSU (w/o an on/off switch) from a working electrical outlet. The 20+4 pin cable is plugged into the mobo and the power button 8-pin wire is also inserted into the correct "pin slot" of the mobo. Doesn't turn on. Swapped with a working PSU (w/ on/off switch) and still no go. Ram, CPU, PCI cards, indicator lights, usb, keyboard, optical drives, hard drive and wires/cables all seem to be in its proper place. Also will it make any difference, let alone relevant at all, if I only have the ram, cpu, indicator lights, PWR button wire and 20+4 pin cable inserted into the mobo while everything else is detached? Otherwise, any suggestions?