Coolermaster GX 750W

Coolermaster GX 750W is a lower quality PSU compared to the Corsair 650TX. And the Corsair 650TX is sized right for your system.
Your PC's power actual requirements should be under 400watts at full load, under 200watts at idle.
So there is something else going on in your case.

What cables did you unplug in your case to get it started with the Corsair PSU?

Not exactly a vote of confidence from some respected review sites:

Coolermaster GX-750 750W review @ JonnyGuru rated 7

Cooler Master GX 750 W Power Supply Review HardwareSecrets wasn't impresssed and suggested an alternate, less expensive 750W PSU.

He didnt say it was DOA. He actually got it running by unplugging some cables inside his case.
If he has something else going on inside his case he might have the same problem with ANY power supply he hooks up.

Or wired up the ON switch backwards.

damit why didnt i test if wiring the on off switch the other way round worked before i sent it back, well i did wire it the right way; with the green on the + and the white on the plain pin.

I have run 2 other power supplies on the same pc and i didnt get any problems, iv used the ocz stealth extreme 600W and the akasa power pax 460w and both work fine with no trouble at all with just 2 hard drives.

I thought it might be to do with atx 2.2 adn 2.3 but why is my power pax 460 psu which is 2.0 working?

the Cosair PSU cabbles i removed from the mother board were the 24 pin and the intel 4 pin
pluging them back in woul let the pc start up.

however shutting down and returning after an hour would have the cosair fail to start up.


I find it weird WR2 that you say
as reviews say the the gtx 470 consumes around 400w during load.
and there are all the other 5 sata drives.

gtx 470 powere consumption here and here.

also i cant get my 460w to start up with all my components on.
i still havnt got a psu yet and plan on getting one this week.

the review recommends the XFX 650W / 750W would getting a 650 xfx be better than a gx 750?

I dont dont care about efficiency thats the last thing on my mind. I place more importance on sound level. the quieter the better, and also the more heat removal from the psu the better for my case.

also i dont want to have the same problem of not powering on.  

so xfx any good?

edit the xfx just has 4 satas id like 6

hmmm ebuyer RMA returns emailed me :
"Following extensive tests by our Returns staff, this item was found to be faulty. Therefore a full refund will be issued once the RMA has closed."

dont know if i should get the cosair again or a different model. I guess theres no harm in trying a new brand

Stay away from Cooler Master PSU. They make one of the crappiest PSU's, especially the Extreme series. They Silent Power Pro and Real Power Pro are better.
Stick to Corsair or Antec for peace of mind.

Corsair TX650W or HX620W FTW!!!

That was 400watts for the WHOLE system - not just the video card. That 400watts is measured at the wall socket and its 400watts AC. PSU use that AC input to make DC power for your parts and if a PSU is 85% efficient that 400 watts of AC is making about 340w DC power for that test system. PSU are rated in DC power they can provide to the PC parts, not in how much AC they draw from a wall socket.
A HDD takes about 10watts max and usually a lot less if not in active use.
If you want to see what the video cards alone use in power check out this data @ TechPowerUp

Since the startup idle loads should be under 200-240w I still think something else is going on in your case. 460w PSU should be plenty of power to boot to idle even if it can't run things fully loaded.

There is a good chance it was 'dropped off' in more ways than one by UPS, etc. Rough handling is a leading cause of early failures.

An option:
Antec EarthWatts EA650 650W $80 and $15 rebate 6x SATA power leads.

 
Switches, unlike LED's, are nonpolarized. It doesn't matter how you hook them up.

It will matter if you don't hook them up across the right header or do some other interesting variation of 'uh ohh'.
"System won't boot" checklist step 17

thanks for that clarification WR2, saves me a bunch of trouble of trying to find a really high wattage psu.
thanks again.

Your welcome. Give us a shout if you have any other questions.

one more thing, im using a core2 duo so ATX 2.2 will work fine right or would i get CPU power on issues? i read ATX 2.3 is for CPU with lower initial power consumptions.

Not an issue at all. Either standard will work fine.