New build, not starting up.. PSU fan runs for a second then dies

[TangoThree]

Just finished setting everything up & went to power on. The PSU fan spins (then stops), the cpu fan spins for a millisecond then stops. This continues repeating every few seconds for as long as its powered up.

I'm using a 2-3 year old 800+W PSU from my previous desktop, everything else is brand new. However I've tried to boot the old system with it and it's working perfectly.

Specs:
gigabyte z97-hd3
i5 4690k
HyperX fury series (2x4gb)
The PSU is a seasonic one, not 100% sure on the model.

I've disconnected everything, checked the chip & the board and everything appears to be fine. I've removed the ram, swapped it around and it's made no difference. Switched from a non-standard CPU cooler back to the one provided by Intel, still no change.

Getting to the stage where I feel I've ran through everything, but nothing's happening.

 

[patrick47018]

Can you test this power supply in another computer?

 

[Yamitime]

Have you attached the 4 or 6 pin cable direct to motherboard around the cpu location?

 

[TangoThree]

ive hooked the power supply up to the tower it came out of and it's running as normal.

I also attached an 8 pin, it says atx_12v_2x4 (only one that seems to match up)