Test built system wont post reliably, HELP!

[flobbadob]

Hello,
I built my system together yesterday, in a test setup config , i5 3570k, cooler master 212 evo, 8gb ram. The system posts fine and i can get into the bios and look at everything. But when the system is powered down then power up again, it does NOT post. The only way to make it post again i have found is to just leave the system off for a bit. I have no idea why this is happening, it could be something to do with the small connectors in the mohterboard, im using my cases connectors and cases buttons to turn it on and off and sometimes when i press the power off button it the system just ignores it, and it takes a couple attempts.

If you need more information ask away, any advice would be appreiciated.

P.S i can post with and without graphics card in this manner so it cant be that, the processor is at an okay tempearture in the bios (30c) , the ram is shown in there, everything is pretty much fine, except it just wont post more than once.

Another concern i had was that the power supply makes an odd high pitch noise when the system is powered down but the power supply is still on , could this indicate a faulty power supply? But how else can i know if its the power supply doing this because everything seems to work fine.

Thanks in advance to anyone.

[Demonwar]

Post the specs of the components.
Any system beeps on the power up?
Sounds like like a PSU issue though someplace, the noise you are hearing could be a bad capacitor.

[flobbadob]

i5-3570k with hyper 212 evo cooler, 8gb patriot black mamba 1600mhz 1,5v ram, corsair tx550m power supply and gigabyte z77x-d3h motherboard rev1

Ive tried a few things, but it seems like when the system doesnt post its stuck in a boot loop, however leaving the system off for a bit will then result in a successful post and into bios, it has been suggested to me to flash the latest bios onto the motherboard, this seems pretty straightforward, what do you think of that idea?

[Demonwar]

Sounds almost that it needs to discharge before booting again if that makes sense. I've not had alot of issues with PSUs, would check everything is plugged in securely first.
After your first boot and shutdown try removing the lead to the PSU and plugging back in straight-away to see if that has any effect

[flobbadob]

no luck , everything is plugged in securely. Do you think the bios flash is an option, or do you think this problem could be psu based.

[Demonwar]

Probably no harm in trying the BIOS flash it anyway as it's a new build.
Have you got another PSU to test with or as you said in your first could be your case buttons but unlikely.

Just to clear up something you said, I assume you have windows installed. You said that you are powering it off with the button, as in not using the shutdown option and just hitting the button?
That could in some experiences/settings could put the computer to sleep rather than turn it off, does it tell you it's shutting down? Maybe your BIOS is struggling to wake/sleep it.

[Scainer]

Process of elimination...
Remove gfx card and HDD

Try with a single sick of ram
Try in a different slot
repeat with a different stick

This in theory would eliminate a ram, gfx and hdd as the cause.

[flobbadob]

i havent installed any os yet, ive tried with either stick of ram in either slots, but as ive said, it cant really be the ram since it shows up fine. Ive been using the case button because shorting out the pins was getting tedious. Its definitely not the gfx, i could post with that (packed it away right now) and im not using a hdd, even if i was i would still be able to post, its just trying to post again after power has been turned off which doesnt work.