MB Popped was it my fault or defect?

FallacyRaver

Prominent
May 12, 2017
1
0
510
Mobo: MSI - 970A SLI Krait AM3+
CPU: AMD - FX-8320 3.5GHz 8-Core
CPU cooler: Corsair H55
Memory: dual channel 8gb G.skills
GPU: Asus 1070 8gb
PSU: EVGA - 500W 80+ Bronze
General: few case fans, 2 monitors, keyboard, mouse, wifi dongle, wireless headphones

Built 1 year 4 months ago, swapped gtx 950 for a 1070 2 months ago. Using the above components my PC cut power. Outlet was fine, desk lamp didn't cut or flicker.
Decided to swap out psu because pressing the power button would only momentarily power LEDs with no boot. (never plugged in mobo speaker so idk if posted or not) everything seemed to be plugged in just fine.

Mobo: MSI - 970A SLI Krait AM3+
CPU: AMD - FX-8320 3.5GHz 8-Core
CPU cooler: Corsair H55
Memory: dual channel 8gb G.skills
PSU: Thermaltake - 750W 80+ Gold Certified Semi-Modular ATX Power Supply

Using the above components, new PSU, no gpu, no monitors or anything else.
Power button, pop sound like a lightbulb bursting maybe sparks(can't remember now), small amount of thick smoke came out. Upon taking everything out, there are small burn marks on the heatsink to the left of the cpu socket. Admittedly I only plugged in the essentials, the 24-pin mobo power, 8-pin cpu power, cpu fan from the H55, and only the case power button with correct - and +. Just to give as much detail as possible.
Testing the old 500W psu the fan turned on when using a 24-pin test clip that came with it, so I assume it was working properly.

Burn Marks, that slight white on the fin: http://i.imgur.com/isAO9NL.png

I have already submitted an RMA, need to ship it out tomorrow.
Just wanna know if I might have done something to cause the problem? I was already planning my next build, but that's on hold until I figure out if I am doing something wrong! Don't wanna set fire to a brand new computer...
 
Solution
Assuming you did not somehow connected 8-pin or 24-pin wrong way (should be impossible, but some people just have talent for impossible feats), I don't see your fault in it. It was either motherboard or PSU problem, but most likely motherboard.
Assuming you did not somehow connected 8-pin or 24-pin wrong way (should be impossible, but some people just have talent for impossible feats), I don't see your fault in it. It was either motherboard or PSU problem, but most likely motherboard.
 
Solution