Solved! Is it a bad idea to hotswap motherboard LED indicator lights while powered on?

[yhelothar]

Swapped the case power LED to the HDD indicator LED while the PC was on. PC crashed and won't post anymore.
I've done this many times with other boards and this is the first time I had an issue. Maybe I was lucky all the other times?

This is on a Z390 Aorus Pro.

 

[VirtualLarry]

Can I ask you this: Whatever possessed you to think that you can hot-swap headed connectors on a mobo? Seriously?

I mean, I've used a screwdriver to short the power-on pins on those headers (who hasn't), but I've never tried hot-swapping them. Never thought that it might be a good idea.

Do you often swap motherboards between cases, while the motherboard is powered ON, or something? I can't really even fathom the need for this.

 

[yhelothar]

Laziness. I've hot swapped so many fans and LEDs over the years without any issues. Maybe I had a freeze a handful of times, but I never had a mobo failure from it.
I hate rebooting. I usually have a huge workspace open.

 

[ch33zw1z]

I wouldn't. power off, unplug, swap cables, plug in, power on. why risk this?

 

[Insert_Nickname]

Bad idea. DuPont connectors aren't meant to be hot-swapped.

I mean, I've used a screwdriver to short the power-on pins on those headers (who hasn't), but I've never tried hot-swapping them. Never thought that it might be a good idea.

I don't have the nerve, so I just use a jury rigged frontpanel from an old case. Complete with reset button, which is actually more useful when troubleshooting.

 

[aigomorla]

ok were talking about headers here right?
like the reset switch, and hdd / power LED?

These would be OK to short / swap while on:

1. The reset button... it works on a short principle anyhow, so if u short it while pc is on, at worst you'll just reset it.

2. The power button.. this works on a momentary switch. Again, its a switch principle.... if the headers detect a short, it thinks the button was pressed, and like you pressing the power button will shut the PC off. I short this all the time when the boards i work with do not have a switch directly on them, and i am too lazy to find my momentary switches.

3. LED - Why can you not plug these in when the PC is on? I am lost, who says you cant?
It is a 3V LED! It draws very little current. The LED will not fry the header, you may however fry the LED if your unlucky. But this is if your unlucky. And some case manufactors are CHEAP as hell and cant use a dual polarity LED, so sometimes you plug them in wrong, and well, it wont light up because the polarity are reversed, and you have to flip them.


So yes, the front headers are OK to swap out as long as you know what headers the are.

 

[Tech Guru]

Maybe previous times you were lucky to face just freezes and nothing more.

Check if any circuit is fried or not.

That should not be the case, but give your board a thorough checkup. if it is just a LED Indicator I cannot see why that would be a problem unless it was interconnected to the power switch. Check that too.

 

[yhelothar]

Ahaha, actually it is fine. Turned out the CPU 8pin modular PSU cable came loose while I was down there.
Kind of disappointed such critical connections aren't clipped where it could just slip out like that.

 

[UsandThem]

Ahaha, actually it is fine. Turned out the CPU 8pin modular PSU cable came loose while I was down there.
Kind of disappointed such critical connections aren't clipped where it could just slip out like that.

All the PSU cables I've seen do have a little plastic clip that locks into place when inserted.

What PSU do you have?

 

[piasabird]

Don't complain when things go wrong if you don't have common sense. You know you should not be messing with the motherboard wired connectors when the power is on. Just because it might work, it does not mean it is a good idea.

Even when you power down the computer there is still power running through the motherboard. Unless you physically unplug the computer or turn off the switch on the power supply things could go wrong. Some capacitors may hold a charge for a while even after power is disconnected.

 

[Ichinisan]

Come on, guys. For LEDs and power switches, just be careful not to short the wrong pins. If that somehow caused damage by shorting the wrong pins, it would happen when you power-on the system anyway.