Question PC won't boot but mobo rgb lights up ?

Dec 25, 2020
I just upgraded my cpu plus my mainboard and added water cooling.
like title says, when I turn on my psu the rgb on my mb instantly lights up, which is already rather weird because I didn't push the power button yet, and If I then push the powerbutton nothing happens at all.
I already rechecked all my connections for about a third time and everything seems to be connected properly.

only things I could think of are broken components (even though I bought every new component brand new), somehow my motherboard has got a short circuit or my psu is broken?

Does anyone have any idea on what else the problem could be?

Intel core I7 10700K
Asrock z490 extreme4
gigabyte rtx2070s
corsair vengance rgb pro 2 x 16gb ddr4
corsair cx650m
nzxt kraken x53
Jan 25, 2021
I have been having issues with what I thought was my power supply but it turned out to be my CMOS battery both times.

First time I had absolutely no power what so ever and figured it had to be my power supply considering that everything else is brand new including my tachia z490 mobo which is exactly what you have. I bought a new power supply and nothing happened. Last ditch effort was to pop the CMOS battery out and purge the dirty power. This is a pain considering you have to completely remove the mobo on our model to take a screw out on the far side of mobo. Once all this was done I could tell it was gonna turn on because I had at least RGB at this point. I turned it on and boom it worked.

Second time happened last night when my cpu crashed and would not restart. The strange thing was that this time all rgb was working but my fans did not spin. So once again I assumed it was my psu. I tested my old psu and the had the exact same results, my rgb lit up but that was it. I took the GPU out and popped out my CMOS battery and instantly started working once I reconnected everything.

P.S If this does work I would reccomend leaving that screw out on the far side of mobo in case this happens again. Paid off for me this once at least.
Disconnect all drives, remove GPU, connect to mainboard onboard HDMI or Display port output...; remove any RGB junk even unneeded fans, anything that could potentially drag down the entire rig or PSU with a short

Drop to single stick of RAM...

Check that pump is connected correctly...

Double check that power switch is connected to correct two pins (you can even temp wire reset switch to the pwr header to test for bad physical switch.., or, temp short those two pins with screwdriver momentarily to attempt power on..

Remove power, remove CMOS battery for 10 min, drain it...