PC won't power on, only lights on mobo/gpu, no fans, silence. Dead mobo? Worked great for 6 months.

Toggle sidebar Toggle sidebar
M

matt.crawford.tx

Prominent
Jan 22, 2018
3
0
510
PC was built for my teenage son 6 months ago, worked great gaming and video editing, then the other day it simply won't turn on. All components were new and have not been abused. I've been going through checking things and I'm thinking the mobo has failed. When everything is plugged in as it should be: leds on mobo and gpu light up, but no fans or psu led, no dr debug, it looks just like it would if I left it plugged in but powered it down. I tested cpu aio pump, radiator fans, case fans with external 12V psu and they all work (and I tried extra fans plugged in and it still wouldn't power up). Voltmeter shows 0V from psu to cpu. If I remove 24 pin atx from mobo and short green to black, then psu kicks on with fan and led, front case fans spin, 12V is going to cpu, no led on mobo or gpu. I tested known known good ram and no change. I've gone through all the checklists and the only thing I haven't tried is clearing the CMOS and swapping in another processor. Is my mobo dead? Is there anything else I can test before I rma the mobo? Thanks!
ASRock Z270 Taichi, i7 7700K, Thermaltake toughpower grand rgb 850, asus gtx980, dual 8gb corsair ram, corsair spec alpha case, samsung 960 evo nvme hdd, deepcool captain 240ex aio cooler
 
Solution
fry178
No, just the psus protection kicking in, and once you "moved" the wires around, it might have been enough to fix it.
If it happens again, swap case or buy a simple switch and "replace" the one in the case..
Sort by date Sort by votes
fry178

fry178

Reputable
Dec 14, 2015
776
12
5,365
Unless the psu is the same as the one installed,
you would have to use all wires from the 2nd one, before you can exclude the psu as cause.

Remove all things not needed for boot.
Only leave ram,gpu and cpu cooler connected.
Remove all plugs from case to board (power and hdd led, reset and power button).
See if it boots when u short power button pins (brief moment), if it boots, you have a short somewhere.
If not, its either board or cpu, small chance the psu.
 
Upvote 0 Downvote
M

matt.crawford.tx

Prominent
Jan 22, 2018
3
0
510


Removed CMOS battery, reinstalled, no change. Unplugged 8 pin power cable, no change. The only way I can get the case fans to spin is if I remove 24 pin cable and manually short green wire to black wire.
 
Upvote 0 Downvote
M

matt.crawford.tx

Prominent
Jan 22, 2018
3
0
510


Now we're onto something.... I just removed all plugs from mobo to case, shorted the power switch pins, and the PC booted up. Then powered off, plugged case wires back into mobo, and now it seems to be fully functional. Turned it on and off with the case power button three times now (still need to hook back up to monitor to be sure its posting though). So what the heck? There was a short in the case wiring, and after unplugging/re plugging the short magically disappeared?
 
Upvote 0 Downvote
fry178

fry178

Reputable
Dec 14, 2015
776
12
5,365
No, just the psus protection kicking in, and once you "moved" the wires around, it might have been enough to fix it.
If it happens again, swap case or buy a simple switch and "replace" the one in the case..
 
Upvote 0 Downvote
Solution
You must log in or register to reply here.

TRENDING THREADS

Latest posts

Moderators online

Share this page

COMPANY
RESOURCES
FOLLOW
Top Bottom