Question Is Overvolting CPUs Safe?

IDProG

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I have a laptop with Ryzen 5700U.

As we all know, laptop CPUs usually come with locked voltage. So, traditional undervolting does not work.

I tried the Ryzen Controller software. I set the TDP to 15W. I tried two configurations:
(1) Default 45A max current
(2) Lowest 20A max current

The second config made he CPU run at 2.7GHz, while the first made the CPU run at 2.5GHz at the same power consumption of 15W. I think both of them produced similar amount of heat.

However, the second config's voltage was around 0.9V, while the first config's voltage was around 0.75V.

The reason in desktop, higher voltage damages CPU more is because the current is the same, right?

Is it safe for the voltage to be higher if the current is lower?

Thank you in advance.
 
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Eximo

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No high voltages are not safe regardless of current. Silicon transistors have a breakdown voltage, so low current high voltage is also bad for them. As they shrink the transistors the voltage has to be lower and lower each generation as the smaller they are the more vulnerable they are to voltage breakdown.

You aren't getting anywhere close to those voltages in a laptop, so you are free to fiddle with it as much as you want really. Excess heat is going to be the main result.

Desktops are pretty loose with the settings, so you can push 1.6 volts through a CPU for a short time for benchmark runs. But you do risk the CPU not surviving the attempt or shortening its lifespan considerably. People that do that are prepared to replace CPUs though.
 
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IDProG

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No high voltages are not safe regardless of current. Silicon transistors have a breakdown voltage, so low current high voltage is also bad for them. As they shrink the transistors the voltage has to be lower and lower each generation as the smaller they are the more vulnerable they are to voltage breakdown.

You aren't getting anywhere close to those voltages in a laptop, so you are free to fiddle with it as much as you want really. Excess heat is going to be the main result.

Desktops are pretty loose with the settings, so you can push 1.6 volts through a CPU for a short time for benchmark runs. But you do risk the CPU not surviving the attempt or shortening its lifespan considerably. People that do that are prepared to replace CPUs though.
So, is 1.2V safe for regular use, even for a laptop?
 
Hey there,

What exactly are you trying to achieve? Faster clocks? Lower temps? For your CPU, even trying will bring practically no results as the laptops thermal envelope can only do so much. Your CPU is rated between 10-25w. Even at 25w you will not be able to get much more increase in clocks.
 
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IDProG

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Hey there,

What exactly are you trying to achieve? Faster clocks? Lower temps? For your CPU, even trying will bring practically no results as the laptops thermal envelope can only do so much. Your CPU is rated between 10-25w. Even at 25w you will not be able to get much more increase in clocks.
Reducing heat by looking at the stock clock speed, then looking at the reduced current's clock speed, then reducing the TDP so it consumes less power and produces less heat at similar clock speed.
 

Eximo

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There will be a point where you can maximize performance per watt, almost certainly not at high voltage.

On a graph this is going to be some rounded triangle shape of voltage, current, temperature. You would need to test a lot of settings to plot it out and the answer is likely close to the stock settings AMD/Laptop manufacturer decided on. There might also be a plateau related to the cooling solution getting saturated.