Jump Start A PSU

Step 3 Read this bit.

IT is important that if you want to connect any components after you've tested your jump started PSU that you switch it off via the mains first then add what ever component you want to then turn it on. if you turn the PSU on then connect the molex adapter to the advice, you will create a nice blue spark and cry when you realise that the component is now dead.

same goes when you are building a PC.

also if you want a 12v supply with upto 5 amps you can cut the red and black wires free (sounds like bomb disposal) of the molex and strip the ends. this will give you a nice supply for what ever.