Question What tests should I do to the motherboard if the power supply damaged my CPU and GPU?

DarMR

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The power supply has been damaged and took the CPU and GPU with it, I rule out that it has been a power surge since the power strip is still working and the other things connected there are in perfect working order. I borrowed CPU and GPU from a friend to test the motherboard and it works fine, but I don't know if VRM is doing its job.

MB: Aorus B450
CPU: R5 3600
GPU: MSI RX 570 8GB OC
PSU: Evga 600W Plus Bronze
 
When a power supply dies and takes other components with it, it is very hard to determine what parts were damaged without a very good multi-meter or oscilloscope. And the knowledge on how to use them.
And both cost way more than a motherboard.
Your new power supply is a low end/cheap unit, but at least it has some protections when it dies.
Can not understand why everyone buys good parts and pairs them with a cheap/low quality power supplies.
A power supply is the most important part of a computer. Without it nothing works.
 
The power supply has been damaged and took the CPU and GPU with it, I rule out that it has been a power surge since the power strip is still working and the other things connected there are in perfect working order. I borrowed CPU and GPU from a friend to test the motherboard and it works fine, but I don't know if VRM is doing its job.

MB: Aorus B450
CPU: R5 3600
GPU: MSI RX 570 8GB OC
PSU: Evga 600W Plus Bronze

Replace the motherboard if the PSU and CPU were both damaged.

The PSU provides +12V to the CPU VRMs on the motherboard which in turn down-regulates that to the low voltages needed by the CPU. If the PSU went bad taking the CPU in the process it HAD to damage/overstress at least one of the VRMs too, the same is true if the CPU went bad taking the PSU with it. The VRM can neither be replaced nor economically repaired so just replace the motherboard to be certain.

The VRM may function for a while, but the devices (FET's) are almost certainly over-stressed and weakened. There are no tests you could do to find an over-stressed FET that might fail when pushed hard with a new (and doubtless more power hungry) CPU. You're very lucky testing your friend's CPU/GPU in that board since the weakened FET's could have failed and taken his CPU. I hope you used a new PSU, at least.

And I'd replace the power strip too. The surge protection devices in even the best power strips have a limited number of 'surges' they can absorb before they have been exhausted. When they fail they do not give any notification of it and the power strip continues to work normally. There may be some at the very high end that do give a notification but they will most likely also have replaceable surge protection devices and you'd know that when you bought it.
 
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Replace the motherboard if the PSU and CPU were both damaged.

The PSU provides +12V to the CPU VRMs on the motherboard which in turn down-regulates that to the low voltages needed by the CPU. If the PSU went bad taking the CPU in the process it HAD to damage/overstress at least one of the VRMs too, the same is true if the CPU went bad taking the PSU with it. The VRM can neither be replaced nor economically repaired so just replace the motherboard to be certain.

The VRM may function for a while, but the devices (FET's) are almost certainly over-stressed and weakened. There are no tests you could do to find an over-stressed FET that might fail when pushed hard with a new (and doubtless more power hungry) CPU. You're very lucky testing your friend's CPU/GPU in that board since the weakened FET's could have failed and taken his CPU. I hope you used a new PSU, at least.

And I'd replace the power strip too. The surge protection devices in even the best power strips have a limited number of 'surges' they can absorb before they have been exhausted. When they fail they do not give any notification of it and the power strip continues to work normally. There may be some at the very high end that do give a notification but they will most likely also have replaceable surge protection devices and you'd know that when you bought it.

In part I have been a bit irresponsible in taking a few precautions and letting myself be carried away by the good evaluation that this power source has. The truth is that the first power supply lasted me almost 3 years leaving the PC on most days.

You will ask, the first power supply?, the context is here: https://forums.evga.com/My-power-supply-damaged-my-CPU-and-GPU-m3585786.aspx something long but detailed my problem .

Damn I wish it would have lasted me 1 year more than I had plans to make an assembly to jump to ddr5. I'll take your advice and buy another board.

I want to buy a UPS that has overvoltage protection, any recommendations?
 
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I want to buy a UPS that has overvoltage protection, any recommendations?
No I don't have any. But the fact remains that surge protectors have a limited life and that will apply to any UPS that features surge protection in it's design the same as with a power strip. That makes an UPS a poor purchase if it's for surge protection. Buy an UPS because you have a computer installation/application that cannot tolerate an unexpected interruption due to a power outage without significant costs accruing.

If you happen to live in a region prone to these power problems get an electrician to install a whole-house surge protection system that protects everything including TV's and appliances. They usually feature replaceable devices that you can easily replace on a seasonal basis. And always unplug the computer when not being used...or at least flip the PSU switch, a 'hard off'. Surges can get into PSU's when 'soft off' and damage them.

To protect your computer when using it buy a modern, top-tier PSU. It doesn't exactly have to be GOLD rated but those that are also tend to have a full range of protections built-in, including robust and effective over-voltage, over-current and over-power protection in addition to their own surge protections.
 
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