PSU help please

[AllPowerfulLamp]

So I ordered a new rosewill 1000W PSU and I plugged everything I need to into my mother board, GPU, etc. a (except I haven't put in a processor )and it won't turn on. I've pressed the powerswitch and everything but it doesn't even light up. I unplugged everything and did the paper clip trick and it worked fine, no odd noises or anything of threat nature. I made sure that the powerswitch was put in correctly. Are there any sugestions or tricks I should try for solving this problem. If it's because I do t have the processor in then please tell me so I can stop worrying.

 

[Aladdad]

it depends on what type of motherboard you have, some will turn on for 3 seconds (fan will spin, PSU will run) but only for like 3 seconds then everything will turn back off...but for most of the motherboard they will not turn on...at all.