PC won't start, no fans, no beeps, tried new MB, PSU, and CPU.

[j-m-x-1]

Hello,

My PC built stopped working after 2 years. It is not starting at all, no fans spinning (including CPU fan) and no beeps. Only sign of life is blinking red light under the motherboard chipset. Light blinks quickly about 7 to 8 times, stops for a second and than blinks again with repeating the sequence all over (MB is ASRock Z270SLIac).

At first I thought that motherboard died so I tried two new motherboards (one identical to my existing one and other Gigabyte Z270) with no luck. Than I thought it is power supply, so I bought the new one and still no signs of life. Next, I tried CPU, I got replacement one from Intel and again, no luck. I pulled memory out (two 8gb DDR4 sticks) and tried each of them individually on each spot with no luck. I tried troubleshooting list to no avail. I'm running out of ideas. I have two questions if someone knows by any chance:

1. What is the meaning of blinking red light under the chipset (MB is ASRock Z70SLI/ac). It blinks 7 or 8 times, stops for a sec and than starts again...
2. Would computer start (beeps and fans spinning) even with bad/dead GPU and or memory?

Also, if anyone else has any other idea please feel free chime in. Getting desperate here. Here are the specs:

CPU: Intel i5 7500
MB: ASRock Z270SLIac
RAM: GSkill DDR4 2x8GB
GPU: Radeon R7 240

 

[terry4536]

Try clearing the CMOS First. Your manual will give the specific procedure for Clearing the CMOS.

The manual will also give specific information on the blinking LED. It likely is an error indicator.

 

[terry4536]

Make sure that all of the motherboard power cables (24-pin and CPU 4 or 8-PIN) are firmly plugged in.

 

[ahmadhijazi0]

Fans should spin even if ram, ssd, hdd, gpu dead. Heck, even if cpu is dead. Sound to me like an issue with your case power button or power button connection to the mobo. Try starting the system by jumping the power pins to bypass the case power button.

 

[j-m-x-1]

Terry, thanks for your suggestions. I already cleared CMOS in two of the MBs I tried. Power cables are firmly plugged in. I checked ASRock manual and they don't have any info on light error indicators. I contacted their (ASRock) tech support but no answer yet.

Would computer start with bad GPU? Even if GPU is not functioning Computer would still start right? Does the same apply to RAM as well?

 

[j-m-x-1]

Fans should spin even if ram, ssd, hdd, gpu dead. Heck, even if cpu is dead. Sound to me like an issue with your case power button or power button connection to the mobo. Try starting the system by jumping the power pins to bypass the case power button.

That is what I thought too, but just wanted to confirm. I wanted to roll out GPU and RAM as a problem instead of shelling $ to buy new RAM and GPU as I already did with MB and PSU.

I tried jumping the power pins, but no success. Thanks anyway, it is good to roll out GPU and RAM as a problem.

 

[j-m-x-1]

Ok I found the problem!!! Let me post it in case anyone else encounters the same problem. It looks like there is defect or short with USB 3.0 front panel. As soon as I pulled out USB 3.0 front panel cable from the motherboard and turned on PC, everything started without any problems.

It is so dumb and I feel as a total donkey after spending 2 weeks troubleshooting everything, buying new PSU, MB, and calling warranty on my CPU. At least it is over now!

 

[ahmadhijazi0]

Glad you figured it out! Nice work!

Don't feel bad though, this was a tough problem in the sense that it's something so unlikely you wouldn't consider it. It was necessary to do the troubleshooting you did to rule out the common culprits. I was close with my case power connection but I wouldn't have said if you hadn't already tested other mobos and psus

 

[anarchy.py]

Ok I found the problem!!! Let me post it in case anyone else encounters the same problem. It looks like there is defect or short with USB 3.0 front panel. As soon as I pulled out USB 3.0 front panel cable from the motherboard and turned on PC, everything started without any problems.

It is so dumb and I feel as a total donkey after spending 2 weeks troubleshooting everything, buying new PSU, MB, and calling warranty on my CPU. At least it is over now!

Thanks Dude! As stupid as it sounds, Same thing happened to me. This is my first build and I was losing my sh** , thinking that I have to undo everything to troubleshoot.

I tried shorting those power pins on mobo with flat head. Didn't work. So I figured power button is fine.

Then,

1. I unplugged the front USB 3 cable - Nothing changed, thought PSU is faulty.
2. But this time, I tried unplugging front USB-C cable - IT WORKED! shh...
3. I turned off my PC and plugged in the USB-C related again in different orientation. - It kept working fine.

Thanks again! you saved a lot of time for me.