GA-Z77X-UD5H won't POST after power off

[rilopes]

Hi, all !!! New to forum and Gigabyte. Just upgraded my system as below ( kept my old EVGA GTX-460 OC Edition and PSU Zalman ZM460B-APS 460 W ):
Gigabyte GA-Z77X-UD5H Rev.1 BIOS F7
i5 3570K
Patriot G2 Series Performance 2x4G PC-12800 Dual Mode
It started Win 7 pre-configured HD and updated drivers. Then set memory to 1600 MHz via BIOS Profile 1  ( originally was 1333 ) and restarted. All OK.
Now, what frightens me: 
After powering system off, I can't get to POST: I hear some "tek" sounds, fans get moving as usual, LED debug display blinks but shows no code and MBIOS and BBIOS led's blink in sequence. After some time it reboots and do the same.
Sometimes I get to post changing onboard switcher to Backup BIOS ( v.  F7 ).   
Tried to clean CMOS, update main BIOS to F8 and strip system to test PSU. None of this worked.


Please help me: don't want to go back to ASUS....

[Dark Mantis]

Hi and welcome.

Firstly I would have to suggest that you change your PSU. The old one (you don't say how old) will be even less powerful than when you first got it and with all the new gear it is probably struggling now.

After replacement I advise you to do an extgended CMOS clear and then load Optimised BIOS Default settings. You might want to update the BIOS afterwards too.

Remove the power cable from the mains supply and then press the power switch on the case for a few seconds just to drain any residual energy in the PSU capacitors.

Once done remove the motherboard battery for one hour before replacing it.
 
Next plug back into the mains supply and boot.
 
You will now need to enter the BIOS by pressing DEL and load Optimised BIOS Defaults.

Make any other changes to the BIOS settings to suit your self like disabling the floppy drive, disabling the full screen logo and making the HDD the primary boot device and then press F10 to save and exit.

[rilopes]

Cheers, mate ! Well, old enough I'd say !  

Today I could start with backup ( F7 ) and main BIOS ( F8 ) after long time system inactive. But...after that it started all over: powering off just made it impossible to POST !  

That PSU's always been solid rock: good power factor, PFC and quiet !!!  

What PSU would you suggest

Thanks !

[ysw521]

you may try to update to f9o bios.

New BIOS on TT forum:

G1.Sniper 3 - F6c
GA-Z77X-UD5H - F9o
GA-Z77X-UD3H - F12j
GA-Z77-D3H - F16a

[rilopes]

Not sure I'm confident enough to flash a beta  BIOS !!!
The thing is: after some hours w/ system off I can turn it on again. The problem only occurs after short time it was turned off. I believe it's the PSU. Anyone ?
I've been looking for a new PSU and found Corsair AX650 good budget. Is that a good PSU for my setup

Thanks, mates !

[Dark Mantis]

Hi


If it is fairly old it is certainly worth changing it.  From what you mention about components I would say that you require at least a 650W. If you are planning to upgrade especially the GPU then go even bigger and make sure that you purchase a decent make and never buy a cheap and nasty power supply they can go wrong and take out all you other expensive components at the same time.  Purchase a good make like Seasonic, CWT, Corsair, Thermaltake, Enermax, Gigabyte, Coolermaster, Antec, etc and try and get one with a single 12V rail if possible. I would advise you to get one of about 650W minimum depending on your hardware demands.

[rilopes]

Yeah, right !I'll look for a good 750W or greater PSU. I'll come back to tell you what happened.

Thanks and "olympic" cheers !

[rilopes]

Back w/ good news: changing the PSU did the trick ! Just bought a new one: Akasa Venom Power 750W. System running like a charm - silent and stable.
i5-3570K @ 4,3 GHz
RAM 1720 MHz

Thanks a lot and cheers ! Thread may be closed.