Motherboard won't boot after installing custom cables

MichaelZeuner · January 19, 2017

Hi all,

So I have been working on a project with the goal to build my computer into my desk. Everything was going well, I created my 24-pin and 8-pin cables for the motherboard and had the pc posting using internal graphics, and a sata power cable (OEM) for the ssd and hdd. I then create a 6-pin, 8-pin, and two sata power cables for powering the graphics card, ssd, and hdd respectively. Since the graphics card is mounted beside the motherboard I have a PCI-E riser cable to make that connection. Anyway, I now have all my cables plugged in and the pc should boot right? Sadly no, I have no power button for this build yet so I press the power button on the motherboard its self. First press the led numbers on the board shows the number 00 for maybe half a second before the pc turns off, second press and nothing happens, no led light up not even for a second. I tried a few more times to see what would happen and most of the time absolutely nothing happens but maybe 1 in every 7 presses the 00 will show up for no more then a second before turning off. Knowing that the problem must be due to one of my newer custom cables I disconnected the graphics card and I went back to a power sata that came with my motherboard. Having had that exact set up booting previously I hoped this would boot, but nope. Next I removed my 24-pin and 8-pin cables from the motherboard and plugged in the OEM cables, still same problem no signs of booting most the time, then occasionally 00 will show for a second before turning off. My first thought is that I must have short circuited the motherboard some how, but I don't see how I could have done that since I tested 24 and 8 pins previously and they worked with no problem. I only plugged new cables into the drives and the graphics card, could a faulty cable not plugged into the motherboard cause the motherboard to short? That wouldn't make sense to me, but hey that's why I'm here, I don't know whats happening. I want to keep diagnosing this problem, but I don't want to start swapping components if I have faulty cables since that would cause me to destroy even more hardware.

What I am currently thinking is to buy a power supply tester and test each cable. I'm assuming something must be wrong with one of them which would have caused this. Once all the faulty cables are found I'll fix them, and try to boot with the same hardware but with fixed cables. If the pc still doesn't boot, and I am confident in my cables, I can start swapping out some components until I find the faulty component. I guess at which point I will have to replace whatever I destroyed (which must be the motherboard if anything right?).

The power supply is a 750 so power shouldn't be a problem, but none of the components should be an issue as this project is using all old hardware that all use to run together with no issue, all I was doing was mounting everything to some wood and creating some custom length cables. Basically, I'm wondering if any of you guys have an idea of what might have caused a lasting issue that even after going back to OEM cables the pc won't boot. Do you have an suggestions on how to correctly diagnose the issue? Do you think my plan of testing the cables and then trying new hardware is a smart approach or would you suggest something different?

Any input is greatly appreciated,

Michael

Lurick · January 19, 2017

I think 00 refers to the CPU, have you double checked the connections to the 8-poin and 24-pin cables and made sure they are fully pushed down? It's possible one of the cables was wired wrong and caused a short so I would take it piece by piece and test them like you mentioned trying. A PSU tester would also be great to know if one of the cables is bad.