Question Motherboards being fried, please need help finding out what's causing it

[melindro]

Hi all, need help finding out what might be frying my motherboards.

I had an old computer which I recently relocated into a Fractal Design Define 7 case because I was planning on attaching 8 hard drives to it. It was an ASUS Sabertooth P67 with an i7-2600k 16 gb of memory and a GTX 1070. Used to be my gaming ring now repurposed as a home server since I no longer play on PC.

Last week I installed a SATA PCI Express expansion card to it and when switching the PC on again it worked for a split of a second and switched itself off.

I could not revive the computer. Tried all the things: CMOS clear different PSU, disconnect everything but CPU and memory to no avail.. The power stand by LED was on and the chipset ran hot but it would not boot. Not even the fans etc. I assumed that the PCI card fried it.

Fast forward a couple of weeks and I ordered a new motherboard, CPU and memory as a replacement. ASUS C246M PRO for its built in 8 SATA ports, i3-9100 and 2x8Gb DDR4 2400MHz memory. In order to test it out first I built it on top of the cardboard case it came with. Motherboard, CPU, memory. Then I plugged it into the spare PSU, switched it on and it booted. I could go into the BIOS, check temperatures and some other stuff. Everything looking great.

I then proceed to move the motherboard in the case. Plug in the PSU that I had in the case. Plug the case front IO panel (power and reset switches, audio and USB). Plug the case fan controller. Then I press the switch on button and again the motherboard boots for a split of a second before switching itself off. I start having a panic attack at this point.

I remove the motherboard from the case to test it with the previous PSU but it won't boot. Fried again. Interestingly the motherboard initially when it worked had 2 LEDs on even when powered off: the power standby and another one called ME (Intel management engine) but now that second ME LED is not switching on either.

So finally my questions are:

• what do you think is causing this? The PSU in the case is frying them? Could it be the case? Maybe one of the fan control circuits or the front panel? If so how come it started happening suddenly?
• What are the chances the motherboard can be salvaged? Could I return it for a refund? Technically speaking one could argue that I broke it by inadvertently plugging it into a faulty case or PSU
• What are the chances the cpu and memory are also damaged? I don't have a means to test them now
• Could I also return the CPU and memory even though they have been used? I guess that one will depend on my shop returns policy. And I'd have to thoroughly clean the CPU thermal paste.

Is there anything else I could test myself? I have a multimeter but no experience in electronics.

I'm thinking of going into a PC repair shop and ask them to test ALL of my components: both PSUs, CPU and memory, motherboard and even the case to try and understand what's causing this. No idea how much this will cost me though, but I don't want to RMA the motherboard only to fry the replacement, or to find out that my CPU and memory were also damaged (even though I guess I could also RMA these if that were to happen).

I'd have hoped modern motherboards would be more resilient? I've been building PCs for many years but this recent experience has left me incredibly disheartened. If I get a new motherboard and eventually PSU I think I might take it all to a shop for assembly as well.

Thanks for your help.

 

[drivinfast247]

Did you install the motherboard stand-offs? If so, are they in the correct positions? Check under the location of the SATA PCI-E card you installed.

 

[Lutfij]

Welcome to the forums, newcomer!

Can you please state the make and models of the PSU's that you've got at hand? Include their age as well. As for your case, do you have all the necessary standoffs mounted in the case whereby they aren't making contact on the underside of the motherboard. Often times a misplaced standoff in a case can cause two contacts under the motherboard to bridge and thus produce a short, if the culprit isn't a bad PSU.

For the sake of relevance, can you please state the specs to your build like so:
CPU:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:

There should be two sets, for a before and after and any spare parts you've used.

 

[melindro]

Welcome to the forums, newcomer!

Can you please state the make and models of the PSU's that you've got at hand? Include their age as well. As for your case, do you have all the necessary standoffs mounted in the case whereby they aren't making contact on the underside of the motherboard. Often times a misplaced standoff in a case can cause two contacts under the motherboard to bridge and thus produce a short, if the culprit isn't a bad PSU.

For the sake of relevance, can you please state the specs to your build like so:
CPU:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:

There should be two sets, for a before and after and any spare parts you've used.

Thanks for your replies. The case has the stand-offs and they were in place. To be clear, the first motherboard was already in the case and using the first PSU, then the issue happened after putting the card in.

With the NEW motherboard, the same issue happened. I moved the standoffs since the old motherboard was ATX and the new one is mATX, but the standoffs are in place. And just to be clear, with the motherboard now OUT of the case, it won't boot. And it's been placed in a surface with no possibility of shorting. I have not tried to install the PCI Card in the new motherboard at all since it already has 8 SATA ports.

PSUs:

• The one in the case is a Seasonic X-Series Gold 660W modular
• The one I tested the new motherboard first with and worked is a Corsair TX650.

 

[SkyNetRising]

• The one in the case is a Seasonic X-Series Gold 660W modular

Did you use original modular cables with this PSU?
Using wrong cables (from some other modular PSU) can kill hardware connected.

 

[melindro]

Did you use original modular cables with this PSU?
Using wrong cables (from some other modular PSU) can kill hardware connected.

Yes, the cables I used are the ones that came with the PSU when I bought it. The other PSU is not modular (even though that one seems to work fine).

 

[SkyNetRising]

Yes, the cables I used are the ones that came with the PSU when I bought it.

Did you buy it new or used?
Might have gotten wrong cables packaged with it.

 

[melindro]

Did you buy it new or used?
Might have gotten wrong cables packaged with it.

I bought it new and was working fine for years.

 

[melindro]

I thought I'd update this: did the paperclip test on both PSUs, and the PSU with which the motherboard was tested with and worked (outside the case) seems to be working fine, whereas the one in the case is indeed not even powering on, doing a strange noise when switched on, but no fans, no power being delivered.

So I guess it's fairly safe to assume the PSU in the case fried both motherboards, and not an issue with the case? I'll try to find a place where they can test if my CPU and memory are still OK, and RMA the motherboard, buy a new PSU, and get it all installed.