CPU, Motherboard and Power supply die at the same time

[tobyhaps1]

PC 1(Won't boot/main)
PSU: Corsair gs 600
CPU: Intel i5-3570 (Socket 1155)
Motherboard: Asus P8 B75-MLE (Socket 1155)
RAM: 8gb Corsair vengeance LP DDR3
GPU: XFX Radeon RX 480 8GB

PC2 (Test pc)
PSU: Dell 240 Watt
CPU: Intel i3-2100 (Socket 1155)
Motherboard: ?? (Socket 1155)
RAM: 4gb DDR3

I left my pc running when i went away for 30min~, when i came back my pc was off.
It didn't boot anymore and the CPU fan only spinned aprox. 0,5 sec everytime i pressed the power button.

I did write down every step.

I got another computer and tried to test my parts on that computer since they were from around the same time.
At first i used the power supply from the test pc on my main and tried to boot and the fans started and kept spinning but no screen/boot and no beeps.
After that i used my powersupply on the test pc, it didnt do anything so the powersupply is definitly broken.

I took the my i5 and put it in the test pc, Still nothing.

I put my main ram in the test pc, The pc worked normal so the ram is working.

I took the i3 and the power supply from my test pc and put it on my main motherboard and the fans started and kept spinning (Same as in step 1).
I got no screen and normally i hear the onboard speaker beep and it didn't this time.

I put the test pc completely back together the way it was before and now that one also won't boot. The fans just spin
really loud/hard and doesn't beep or show a screen.

Recap:

My i5 doesn't work in the test pc and the i3 from the test pc doesn't work in my main pc. So i have a feeling my i5 and the Motherboard from my main pc are broken.

But now my test pc also doesn't want to boot.

The RAM, HDD and fans are still working.

Can it be that my CPU, Motherboard and Powersupply all broke at the same time, There were no lighting strikes and all the other appliances/ computers still work that were hooked to the same socket.

Does anyone know any other methods to test my parts?

Can my Motherboard be so broken that it breaks every CPU i put in it?

If i'm being too vague just ask, Thanks!

 

[drea.drechsler]

I can imagine the motherboard CPU VRM failing to a short, over-volting the CPU causing it to fail and in turn over-loading the power supply causing it to blow an over-current protection fuse.

In such a scenario swapping of parts might easily cause even more failures: imagine, for example, putting a perfectly good CPU into the motherboard with the bad VRM after finding and replacing the power supply fuse. It could very easily fry another processor.

 

[DRagor]

Since you don't know what MB you have in PC2, you can't tell if i5 is dead, as it could be just the PC2 motherboard has BIOS that does not support it - unless the PC2 did not even start at all when you put i5 there?
When you put i3 and Dell PSU in PC1, did you removed GPU? Because that PSU would not have enough power for it and that could be the reason PC1 did not boot.

Clearly the PC1 PSU has failed, and it could damage any number of other components along. But that does not mean CPU/MB are gone, it could as well be only GPU that died. Since your board has iGPU, you should remove GPU and do all tests without it.

As for PC2 not working now - reset CMOS and double check all cables.

 

[tobyhaps1]

When i left the GPU in it didnt do anything and when i removed it it just started spinning but still didn't show a screen or beep. When i put the i5 in pc2 It didn't do anything is just spins the fan for 0,5 sec when i press the button. The motherboard is from a dell optiplex 790 i3 i think the number is D28YY
here is the guidebook http://clascsg.uconn.edu/download/specs/O790.pdf

 

[tobyhaps1]

Btw. I did al my test without the GPU in it

 

[DRagor]

When i put the i5 in pc2 It didn't do anything is just spins the fan for 0,5 sec when i press the button.

That's not a good sign. Did you connect CPU fan when doing that? If you did, seems like i5 is toasted.