New build woes - one dead mobo already, same thing again

smr

smr

smr

Soldato
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Hi,

So, am building a rig for someone, basically it got dumped on me as the lad fitting it didn't know what he was doing.

Faulty mobo first time around - the computer would start up and stay on for several seconds and then turn off, and then reboot itself and repeat this. Then smoke started coming out of the back of the mobo near the backplate, so the mobo got RMA'd.

After two months (unbelievably) they said it was a faulty mobo and refunded.

I bought a new mobo for them, and it's doing the same thing. Turn on, several seconds stays on, I can see the RAM LEDS glowing and LEDS on the mobo glowing, no signal on monitor, and then reboots itself, repeat.

Things I have tried...

I've tested the PSU with my rig and it works fine on there.

I've tested both RAM sticks individually.

So what's causing this? Faulty CPU ?
 
If the smoke originated from that area, it could have been a VRM dieing, and it could have taken out the CPU or anything else for that matter. Make sure you've also double checked the simple things, ATX connections for CPU / GPU etc.
 
Trying it out of the case and it's still the same. I don't know why the fans aren't coming on on the cooler.
 
when I short the pwr pins to try and turn the computer on the RAM LEDS light up but the PSU fan nor the cooler fans turn on, then after several seconds the computer makes a light clicking sound (probably the PSU) and then the RAM LEDS turn off, and the fans on the PSU and cooler then just jig from side to side for a second... then it tries to restart itself, the RAM LEDs come on, several seconds later it again turns off and the fans jig for a second and it repeats.

I've tested the PSU in my rig and it boots it up fine.
 
Ok so the PSU fan spins up now (it had an ECO switch on the PSU which I turned off) but not the cooler and otherwise the same as above. With both RAM sticks in or one at a time.
 
No I haven't tried a different CPU. I've just tried a normal stock fan on one of the fan headers and that spins up and comes on fine, so maybe the coolermaster cooler has had it.

If I plug the coolermaster into the CPU fan header I can hear the water but if I plug it into the correct CPU Pump header I don't hear anything so not sure if the coolermaster has completely gone but the fans definitely aren't working.
 
It sounds like the first motherboard has fried the CPU.

However to be on safe sound, I would take your existing PSU, and test on the new rig.

Also to check, have the switches / case LED lights been connected to the motherboard correctly?

More also. Have you installed the memory in the correct DIMM slots / slot? I would test with 1 DIMM first, however if it's in the wrong slot the computer may not start. In the confusion of trying to diagnose a fault computer it's easy to have the memory installed wrong.
 
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JasonM said:
It sounds like the first motherboard has fried the CPU.

However to be on safe sound, I would take your existing PSU, and test on the new rig.

Also to check, have the switches / case LED lights been connected to the motherboard correctly?

More also. Have you installed the memory in the correct DIMM slots / slot? I would test with 1 DIMM first, however if it's in the wrong slot the computer may not start. In the confusion of trying to diagnose a fault computer it's easy to have the memory installed wrong.
Click to expand...

Yes I'd thought of that but you just inspired me to try it. Same thing. So that rules out the PSU for definite. I can't believe the new mobo is faulty, the RAM LEDS light up and there's a red pulsing glow coming from the mobo as well.

So it probably is the CPU. The thing is a new CPU is £180 and if that doesn't fix it it means I've just spend £200 on a new mobo and £200 on a CPU.

I've tried each RAM stick in one at a time in different DIMM slots (there's 2 DIMM slots) so I doubt two would be defective.
 
smr said:
Yes I'd thought of that but you just inspired me to try it. Same thing. So that rules out the PSU for definite. I can't believe the new mobo is faulty, the RAM LEDS light up and there's a red pulsing glow coming from the mobo as well.

So it probably is the CPU. The thing is a new CPU is £180 and if that doesn't fix it it means I've just spend £200 on a new mobo and £200 on a CPU.

I've tried each RAM stick in one at a time in different DIMM slots (there's 2 DIMM slots) so I doubt two would be defective.
Click to expand...

Just other things to check.

Do you have all motherboard fan headers disconnected? Just incase a fan is stopping the computer from booting.

You have nothing extra connected to the PSU, such as a water cooling pump?

Nothing extra connected such as a DVD player?

What graphics card are you using? Or are you using the CPU on-board?

Without sounding like Mr Obvious, but have you disconnected / reconnected the BIOS battery?
 
JasonM said:
Just other things to check.

Do you have all motherboard fan headers disconnected? Just incase a fan is stopping the computer from booting.

You have nothing extra connected to the PSU, such as a water cooling pump?

Nothing extra connected such as a DVD player?

What graphics card are you using? Or are you using the CPU on-board?

Without sounding like Mr Obvious, but have you disconnected / reconnected the BIOS battery?
Click to expand...

I can try it without any fans connected, even the CPU / water cooler fan disconnected?

Nothing extra connected to the PSU, just the 24 pin ATX and 8 pin CPU Cable.

No peripherals or anything

No gfx card connected, just the onboard. Actually I think I probably should try the gfx card in my rig to make sure that's ok.

Afaics there's no bios battery but there's a clear cmos button on the rear I/O panel which I have tried pressing.
 
Ok I've just unplugged absolutely everything just leaving the CPU and the 20/24 pin ATX PSU Cable connected.

Same thing. So I guess it's the CPU as I know the PSU is ok in my rig, well, either the CPU or the mobo?
 
Where does one stand if the mobo blew other components bought for a computer build yet the mobo RMA took about 2 months so the other components for the build are out of their 30 day return etc?
 
Right, I've taken the Coolermaster pump and plugged it into my rig (not the cpu cooler) but I've just plugged the fans in, they spin.

So that's ok on my rig, but it doesn't work with this new mobo. Yet if I use a basic stock fan on the chassis fan connector on the mobo that does work. WTH.

Maybe it is that this new mobo is also faulty?

Surely a defective CPU can't stop the fans from spinning on the Coolermaster cooler?
 
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Have you removed the cooler backplate to verify it's not that which is shorting something on the back of the motherboard? Wouldn't be the first time that a Coolermaster backplate has made improper contact with components at the back of the board although am only familiar with it happening on some of their air coolers, and depending on the motherboard as well. Just something else to try.
 
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