No display during cold boots

Yep sounds very much like a GPU problem mate.
The paper clip trick is only the power on - there is circuitry inside the PSU that tests the volts etc before the machine can be turned on by the Power_Good at pin 8 on the 24 pin plug. The system is only fired once that signal is reached at pin 8.
Otherwise the machine could be exposed to volts outside of any normal parameters as most of the rails have to run within a very tight +/- percentage of the stated volts.
The Power_Good voltage has to be above 2.4v and below 6v for the purpose of turning on the machine ie booting.

I too concur with Icit2lol; at this point its probably something having to do with your or gpu. Most graphics cards require a certain amount of voltage that is set voltage(parameters) in order for them to work properly which is also why you need to make sure your power supply is putting out the right amount of voltage as well.

As Matt says mate and you might try this to figure out what power PSU you need.

eXtreme Power Supply Calculator just enter the gear you have and it will spit out what power (wattage) PSU will be needed - minimum.

Hmm that doesn't sound like a large power consumption at all I would have thought it would have been closer to the max there was.

The Antec sounds a decent one to me although like I said I would have stuck to a Corsair but with 60 amps 12+v on tap you should have more than enough power to play with.

Anyway let us know how it goes.

Ok mate I still think the readout you got before was low for what you have you might try a rerun with it and make sure everything is put in - some of it is pretty technical and some stuff it seems irrelevant I know but worth looking at.

If you want to keep an eye on the volts from the new PSU and other stuff in the machine run HW Info HWiNFO, HWiNFO32/64 - Download < get the right bit version > close the right hand window and click on Sensors > scroll down the window that opens and check the volts.

The other devices can be viewed by opening them out in the left hand side window see my pics.

Well mate lets say so far so good and don't let us count out chickens yet but it is looking to be that way.

I don't know if you run any cleaners for the system or on call malware checks but these are worth keeping.

CCleaner - Download < download from piriform will keeps the temp files and rubbish at bay this is the tutorial for it CCleaner - Delete Junk Files just one thing before you run the cleaner make sure to Analyse > Options > Cookies - and any that you use for sites you need passwords for save to the right and liist by highlighting them then click the arrow right. When done go back to Cleaner and run it. (See pic)

Theses are there on call malware scanners I use and a lot of the others use

http://www.superantispyware.com/

http://www.malwarebytes.org/products/malwarebytes_free/

http://www.bleepingcomputer.com/download/adwcleaner/

ADW download frombleeping computer delete any rubbish found with the malware scans
the ADW not so much and you will need to download it each time you run it if you have to.

This is handy too Optimize Windows 7