Question New build, was working briefly, now not so well!

Apr 1, 2019
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Parts: - Coolermaster N200 Case,
  • AMD Ryzen 1700,
  • Gigabyte Auros B450 M,
  • Seasonic 520W 80+ -
  • Corsair - Vengeance LPX 8 GB DDR4-3000 Memory
  • WD Blue 250 GB M.2
  • EVGA GeForce GTX 950 2 GB
So I received everything, except the case in a timely manner, so decided to build and install OS etc, whilst case was on its way. Built in a couple of hours, with OS, drivers etc. all done. So I turned off and waited for case. Case arrives few days later, I install into case and power on. All Ok, except I notice I hadn't plugged the rear fan (which was connected to mobo with 4 pin) into the molex daisy chain, which the front fan is plugged into and spinning. So I power off the system, plug the system fan in to the molex chain and go to power on. There is a blip of power, lights come on fans turn and then it all goes off and stays off. OH O!

Troubleshooting, has led me unplug everything and remove from case, all that remains on my table is the Mobo, CPU & obviously PSU.

  • I plug in the PSU, to there is power to the mobo, a white light flashes on the mobo. (I think this is normal, but not sure)
  • I jump the mobo with a screwdriver and a red light flashes on the CPU indicator on the mobo and the fan lights up, literally for 0.1 seconds then goes off.
  • If I try to jump the mobo again, I have to totally unplug the PSU and try and jump with mobo without any power a few times, (almost as to discharge the mobo) before it lets me try again.
tested PSU, that's ok. unfortunately, I can't test either the mobo or CPU on another system at the moment.
What do we think the issue is here? it's as though I shorted something by plugging in the fan. if I had to return a part would it be the CPU or Mobo?
Thanks in Advance.
 
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cdrkf

Honorable
Parts: - Coolermaster N200 Case,
  • AMD Ryzen 1700,
  • Gigabyte Auros B450 M,
  • Seasonic 520W 80+ -
  • Corsair - Vengeance LPX 8 GB DDR4-3000 Memory
  • WD Blue 250 GB M.2
  • EVGA GeForce GTX 950 2 GB
So I received everything, except the case in a timely manner, so decided to build and install OS etc, whilst case was on its way. Built in a couple of hours, with OS, drivers etc. all done. So I turned off and waited for case. Case arrives few days later, I install into case and power on. All Ok, except I notice I hadn't plugged the rear fan into the molex daisy chain, which the front fan is plugged into and spinning. So I power off the system, plug the system fan in to the molex chain and go to power on. There is a blip of power, lights come on fans turn and then it all goes off and stays off. OH O!

Troubleshooting, has led me unplug everything and remove from case, all that remains on my table is the Mobo, CPU & obviously PSU.

  • I plug in the PSU, to there is power to the mobo, a white light flashes on the mobo. (I think this is normal, but not sure)
  • I jump the mobo with a screwdriver and a red light flashes on the CPU indicator on the mobo and the fan lights up, literally for 0.1 seconds then goes off.
  • If I try to jump the mobo again, I have to totally unplug the PSU and try and jump with mobo without any power a few times, (almost as to discharge the mobo) before it lets me try again.
tested PSU, that's ok. unfortunately, I can't test either the mobo or CPU on another system at the moment.
What do we think the issue is here? it's as though I shorted something by plugging in the fan. if I had to return a part would it be the CPU or Mobo?
Thanks in Advance.
Just a daft question, but you were saying all you have left is cpu, motherboard and psu... you do also have the graphics board and ram installed and the cooler on the cpu correct? Just in case you were unaware, as you are using the R7 1700 you can't plug a screen into the onboard video ports as that cpu has no integrated graphics chip and there isn't one on the board either. Without a graphics adapter (and memory) the machine won't be able to boot.

I'd also be surprised if a fan connected to a Molex would short out the motherboard or cpu, as that is on a separate line (although the CPU does have a 12V input on the motherboard)...
 
Apr 1, 2019
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Just a daft question, but you were saying all you have left is cpu, motherboard and psu... you do also have the graphics board and ram installed and the cooler on the cpu correct? Just in case you were unaware, as you are using the R7 1700 you can't plug a screen into the onboard video ports as that cpu has no integrated graphics chip and there isn't one on the board either. Without a graphics adapter (and memory) the machine won't be able to boot.

I'd also be surprised if a fan connected to a Molex would short out the motherboard or cpu, as that is on a separate line (although the CPU does have a 12V input on the motherboard)...
Hey thanks for replying, yes I'm aware the 1700 has no graphics, at the moment I can't even get it on, nevermind display lol. I stripped it to minimum, so I could try and at least try and get the mobo running. I tried with and without RAM.

This is what I thought, how could I break the mobo or CPU with the molex power. The only link was the rear fan connected to the system fan port on the mobo (as well as the molex).
 

cdrkf

Honorable
Hey thanks for replying, yes I'm aware the 1700 has no graphics, at the moment I can't even get it on, nevermind display lol. I stripped it to minimum, so I could try and at least try and get the mobo running. I tried with and without RAM.

This is what I thought, how could I break the mobo or CPU with the molex power. The only link was the rear fan connected to the system fan port on the mobo (as well as the molex).
You didn't connect the rear fan to both the molex and motherboard did you?

Edit: if that is what happened, then I think you may have damaged your motherboard- the motherboard fan connector provides power to the fan as well as controlling the speed. Many case fans include a molex to use instead of the motherboard header, as not all motherboards include outputs for case fans (or they may only offer a single case fan header). If the rear fan wasn't running when you set up your machine in the case, this was probably down to the bios temp settings, which to keep noise down, will turn off any motherboard controlled case fans until the temps reach a threshold level (so the case fans would be off for light duty but will then kick in if you start working the system harder).
 
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Apr 1, 2019
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You didn't connect the rear fan to both the molex and motherboard did you?

Edit: if that is what happened, then I think you may have damaged your motherboard- the motherboard fan connector provides power to the fan as well as controlling the speed. Many case fans include a molex to use instead of the motherboard header, as not all motherboards include outputs for case fans (or they may only offer a single case fan header). If the rear fan wasn't running when you set up your machine in the case, this was probably down to the bios temp settings, which to keep noise down, will turn off any motherboard controlled case fans until the temps reach a threshold level (so the case fans would be off for light duty but will then kick in if you start working the system harder).
I did indeed, in my haste I didn't unplug it, I didn't think it would short the mobo, just maybe blow the fan. It wouldn't have caused any damage to the CPU in your opinion? I will get the motherboard returned then and not say a peep about what I did🤫

Edit: Just found this on the forum. https://forums.tomshardware.com/threads/i-might-have-accidentally-fried-my-motherboard.3020771/
seems similar to what I did. However, the Mobo still lights up when it has power, before I switch it on and it goes dead.
 
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cdrkf

Honorable
I did indeed, in my haste I didn't unplug it, I didn't think it would short the mobo, just maybe blow the fan. It wouldn't have caused any damage to the CPU in your opinion? I will get the motherboard returned then and not say a peep about what I did🤫

Edit: Just found this on the forum. https://forums.tomshardware.com/threads/i-might-have-accidentally-fried-my-motherboard.3020771/
seems similar to what I did. However, the Mobo still lights up when it has power, before I switch it on and it goes dead.
It's difficult to know but I think your cpu will probably be ok, it's easy to do these kinds of things, I've killed a few components over the years!
 

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