How to check the CPU temperature in real time without using any software!

No, that's not the right way to do it. A closed lid ensures airflow inside the system unit and, as a result, more efficient cooling. When the lid is removed, this airflow is lost, and the fans working to exhaust and intake (if any) end up working in vain. Moreover, the air temperature is still high in summer, no matter what. So, removing the lid can only be harmful; I myself once kept the lid off out of ignorance, and when it was time to upgrade my computer, I faced criticism about this. I also looked at the opinions of experts online.

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And didn't you think that you can rearrange the fans? Who needs intake and exhaust in the heat, when it's over 40 degrees...? Sometimes, in a cramped system unit - the size of a *walnut* -)))
You take a good 120mm fan and glue it to the front of the motherboard. 100% airflow. And 50% less noise. Proven over the years.
With this combination, the temperature on the motherboard and the processor decreases noticeably. And all this is intake and exhaust :) For;
Overclockers:D

You know, I didn't regret spending money on a real cooler. And I don't regret it.
I bought a *Zalman 9700 LED*. This is more than 500 grams of copper (Cu) + a high-quality and fast (with a regulator), quiet fan. And you know what? It was worth it. I have a dual-core 3 GHz processor. The temperature on it is always *normal*, under any load:smile20:
So, I advise you not to do it randomly, but based on what has been tested by me personally)

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Ivanhoe, I said, do it anyway. Okay.