I connected a PCI cable into the motherboard's 4-pin OC connector and noticed smoke - what went wrong?
I connected a PCI cable into the motherboard's 4-pin OC connector and noticed smoke - what went wrong?
Hi Guys,
I've upgraded my PC myself for about 3 to 5 years. I just bought an ASUS X670 P Wi-Fi with a 7800x3d chipset to upgrade my old Intel system. It was late and I was a bit stressed. I found an extra 4-pin (ATX-12V-2) connector next to the standard one and connected a PCI cable. It fit perfectly... -.-
After turning it on, no fans were running. But the PCI cable smoked and melted quickly, so I cut off power. The ATX/PCI plug got a bit burnt. After cutting the cables and restarting, the PC worked fine.
However, if I try to restart now, it doesn't work. I have to force shut it off or turn it off manually after a while.
Armoury crate update isn't working, and the BIOS update isn't either. Sometimes I hear one long 3 short beeps (maybe GPU?).
Question: Did I break something? Or are there separate issues? Customer support is gone—I think ;-)
Thanks, guys! Sorry for my English.
Regards, PrvtCowboy
pictures imgur
if there was smoke and melted cables, definitely!
continuing to use this PSU could cause some very heavy damage to the rest of connected components.
i would remove this thing asap and get another unit.
it's possible that motherboard and/or other components are already damaged.
15 years later, for sure.
Hi,
as you mentioned, Mobo etc could be affected.
I purchased a new Mobo and PSU. It saves my money and frustration.
Thanks!
Main Question: How did the Mobo get damaged? I just want to grasp what happened technically. Sure, it received "wrong power."
I connected the ATX 12V with the four pins from the 6-pin PCIe card. Everything matched perfectly. Are both 12V?
Was there too much power or heat? But does the ATX require more power than the PCIe can supply? Could a smaller PCIe be causing more damage than it should?
In a German forum I read the only possible issue was cable damage due to security features from the PSU. Maybe they discuss newer power supplies;
Thanks for clarifying what I don’t fully understand!
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If that is the situation, it seems you connected the +12v wires from the ATX cable to the ground connectors on the PCI cable. This means the live wire is passing through the ground connector on the hardware. It appears there might have been a short circuit and the wire became extremely hot, possibly melting.
It was the incorrect polarity that poses a serious risk to electronics operating on DC current. Make sure you read and understand those manuals thoroughly before beginning any work. Even after many years with PCs, I still refer to manuals for every component before purchasing, as they highlight all potential issues that might arise.
If something fits, it doesn't necessarily mean it belongs there.
You swapped the wires for +12V and ground and made them short.
This is similar to connecting both ends of the same wire into a power outlet.
Edit: For anyone reading this — don't do that. It's very risky.
In such situations, every detail must be verified to ensure full functionality.