No video, No beep, Asrock 990FX Extreme3

[renks051]

When I rebuilt my computer I got no video no beeps, nothing. I already tried CMOS reset (with a battery and also CMOS jumper). I went minimalistic and removed everything from the motherboard, there is only PSU connected and CPU. I have installed speaker and I still get 0 beeps when I power computer. I added 1 stick of RAM and still nothing. This computer worked yesterday.
So now I have 0 idea what to do next.
PC Specs:

Asrock 990FX Extreme3
FX 8320
Crucial 1600Mhz 4GB x2
Fortron 650W Silver+
270X Dual X 4GB

 

[mvbighead]

Check to make sure all power leads to the board are good. Also try a spare PSU if you have one. Anything should work, just something to get it to power.

Make sure you turn off the power at the PSU switch, attempt to power the board (to remove any remaining 'charge'), and remove the battery to reset. That should ensure a successful reset.

Also, try the RAM in different slots.

 

[renks051]

How long time does it take to reset CMOS?
Can it even take 24 hours?
Do I really need CMOS battery?

 

[WT]

You haven't ruled out a broken power button on the case itself. Remove the power on pinout and use a straight screwdrver to short those same two pins to see if it will boot. I've had it happens one ... its rare, but it's still a possibility.

 

[mvbighead]

How long time does it take to reset CMOS?

with the battery removed and power at the power supply off, an attempt to turn on an ATX board will 'decharge' the board so that no power remains. Or, shorting the pins for the CMOS also works, but the method I suggest is guaranteed to lose any stored settings.

Can it even take 24 hours?

No. When the board is 'decharged', the board cannot retain those settings. As long as you do those things, the CMOS should be cleared.

Do I really need CMOS battery?

Yes, elsewise any loss of power (flipping the switch in the back or power outage) will result in you needing to configure boot options and other configurations.