Pulled motherboard power pins while power still on

[Brick_Cliffton]

So I've built a few computers, I have some know-how, but not a lot. Just enough to be dangerous apparently. My most recent build, well, it won't start. Nothing, not the fans for either the PSU or the CPU. I was talking with tech support, and the guy indicated I should remove the motherboard from the case and try starting it with everything plugged in while it was on a cardboard box, to avoid any possible shorts the motherboard might have with the case. I said I'd call back after trying and hung up.

I had no problem taking the motherboard out of the case, but, when I flipped the switch, nothing happened. I was pretty angry at this point, because this is the first time I've had a problem like this. I thought I'd isolated the problem to either the motehrboard or PSU (why else wouldn't anything power up when I flick the power switch?). Someone showed me the trick about shorting pins 15 and 16 on the 24 pin connector if you want to test your power source, so I unplugged the 24 pin connector and the 8 pin, shorted the 15 + 16 pins with a paperclip, and bingo, PSU fan starts up, and my frustration starts to fade because I think it must be the motherboard then. And then I also heard the hard drive or disc drive start to spin up. It took me a half a second to realize what that whirring noise was, to realize that I'd left the hard drive and disc drive still connected to the PSU. I immediately flicked the power switch, and the hard drive or disc drive (not sure which, or both) stopped spinning. But then it also dawned on me, the 24 pin and 8 pin must've been live when I pulled them, so there might've been power to the chip and RAM as well (not sure if that's actually the case, because, as I mentioned, I can't get the thing to boot, and it seems like a motherboard problem).

I was trying to fix one problem, and might've caused a dozen more. What actually happens when you pull the plug on something like that live? Did I just accidentally bork my chip, motherboard, and hard drive in one fell swoop?

Edit: there were requests for build specs. AMD FX8350, Radeon R9 280, 16 gb of RAM over 2 sticks, Gigabyte 990FXA-UD3, Antec 620 continuous watt PSU, NZXT Sentry-2 (because the 990FXA only comes with 2 fan headers and my case has 4).

Edit 2: I'm a dingus. PWR_FAN header doesn't mean what you think it means.

 

[Illuminations]

Could be the case, however I slightly doubt it. It's probably like any power-shortage.
It's all about luck, really.
If you can, try to test the parts in another build, or with some other parts, until you find the faulty one (If there is one).
But, if you put it all together, can you start it?
(Sorry if I misunderstood the question ^^)

And, Im not the best person ever to answer this. Built like 3 rigs only; However it might help

Good luck, and have a Great Day!
Axel.

 

[Zerk2012]

That should of done no damage.
Hook everything up and try jumping the power pins out instead of using the case switch.
When you need help like this its best to list everything in the PC.

 

[Ubrales]

Install everything in a different case and then try to power up. To me it appears that the "Start" button on the case may not be plugged in right, or is bad.

 

[Brick_Cliffton]

Could be the case, however I slightly doubt it. It's probably like any power-shortage.
It's all about luck, really.
If you can, try to test the parts in another build, or with some other parts, until you find the faulty one (If there is one).
But, if you put it all together, can you start it?
(Sorry if I misunderstood the question ^^)

And, Im not the best person ever to answer this. Built like 3 rigs only; However it might help

Good luck, and have a Great Day!
Axel.

Thank you for the response.

When I put it all together, I can't get it to start. It won't go to BIOS, and none of the fans even start. The best I can do is plug the mouse into one of the USB slots, and it glows (like it's supposed to). I don't think the problem is insufficient power - I checked my requirements like a dozen times, and everything indicated I'd only need 450 watts, and my PSU is rated for 620.

That's part of my question, but the bigger concern I have is that I accidentally pulled the motherboard power pins while they were still live. Is that going to cause any damage to the motherboard, chip, RAM, or anything else?

 

[Zerk2012]

Do what I said take a screwdriver and junp the power pins out on the motherboard.
Double check to make sure your on the right pins in the motherboard manual.

 

[IamTimTech]

It didn't hurt to pull out the 24pin while it had power, especially if it wasn't on. You have your 4/8pin CPU power plugged in right? Please list the specs of your machine.

 

[Zerk2012]

Install everything in a different case and then try to power up. To me it appears that the "Start" button on the case may not be plugged in right, or is bad.

Their no need to do that when you can just jump them out or even use the reset switch hooked to the power connectors.

 

[Brick_Cliffton]

That should of done no damage.
Hook everything up and try jumping the power pins out instead of using the case switch.
When you need help like this its best to list everything in the PC.

Thank you!

It's an AMD FX8350 with a Radeon R9 280, 16 gb or RAM over 2 sticks, with a Gigabyte 990FXA-UD3 for the motherboard. The PSU is rated for 620 continuous watts.

I tried to short the power pins once after one of the tech support guys recommended it. I got it to work... exactly once. It launched to the BIOS no problem. They recommended I switch the power and reset cables for the internal connectors, the ones that go to the front panel and leave the power cable unattached, and just use the reset switch as the power button until a replacement arrived. When I tried that and pressed the reset button though, I got nothing. I removed the internal connectors and tried to short the two pins with a flathead a second time, and the second time, nothing happened. This second attempt was before I pulled the live power pins and thought I messed everything up terribly, so the two are unrelated.

Any other thoughts?

 

[IamTimTech]

You should disassemble your build and start over. Take everything out put the motherboard on the motherboard box with just the CPU and RAM in, plug in your 24pin and CPU power connectors and then plug in your monitor and use a screwdriver to short the power button front panel pins. Does it come on? I bet it will and thats good. Now connect your hard drives with the sata cables and the sata power cables and see if it posts. If it posts again awesome, shut it off and now plug in your GPU and connect its connectors and change your monitor cable from the motherboard to the GPU. At this point your machine should be posting and working properly with all of the key components connected.

Now just take it all apart and carefully put your motherboard back in, make sure you have only the motherboard posts in that you need and that they are all secured nice and snug (Not too tight) then repeat the process you just tried with everything out of the case.

 

[Brick_Cliffton]

You should disassemble your build and start over. Take everything out put the motherboard on the motherboard box with just the CPU and RAM in, plug in your 24pin and CPU power connectors and then plug in your monitor and use a screwdriver to short the power button front panel pins. Does it come on? I bet it will and thats good. Now connect your hard drives with the sata cables and the sata power cables and see if it posts. If it posts again awesome, shut it off and now plug in your GPU and connect its connectors and change your monitor cable from the motherboard to the GPU. At this point your machine should be posting and working properly with all of the key components connected.

Now just take it all apart and carefully put your motherboard back in, make sure you have only the motherboard posts in that you need and that they are all secured nice and snug (Not too tight) then repeat the process you just tried with everything out of the case.

So I took everything apart, and yes, it did work! But after a bit of experimenting, it seems to work because I UN-plugged the power fan connector. On the motherboard, there is a 3 pin header, PWR_FAN, which the motherboard manual says is "a 3-pin power fan header." There was only one connector on my PSU that would fit there, and it's at the end of 3 molex connectors which I assumed were for fans, specifically, the PSU fan. Apparently it isn't? Well in all regards, boots up great every time I short the power connectors when that ISN'T plugged in where it looks like it should go, so problem solved! Thank you!

 

[Illuminations]

Glad you solved it!
Good luck in the future!

 

[IamTimTech]

LOL, you plug fans into that man, not your power supply

 

[Brick_Cliffton]

LOL, you plug fans into that man, not your power supply

Yeah, I'm a dingus. So dumb question, but what exactly is a power fan then, and why is it distinguished from a system fan? There's the CPU fan header (got that one right), and system fan headers (got those right, case fans work), and now this mysterious pwr_fan header, which I assumed was for the power supply unit fan because, well, it's labelled power fan, and it was right next to the 24 pin connector.

 

[IamTimTech]

Just another fan header you can plug a 3pin fan into

 

[plywrlw]

Tee hee, think you plugged a floppy power connector into the motherboard. Oh well, easily done!

I don't think it means a "Power Fan" I think it means "Power for a fan" either that or it means "PWM fan" which is one with 4 pin slots.

Glad it's OK now

Always read the mobo manual....twice!