CPU overheating with age?

[hucker]

Odd, my CPU was getting to 100C, so I bought a big CPU cooler (twice the normal size). That took it down to 80C, but it's gradually worked it's way back up to 100C again. Now I've slowed the CPU down to 85% of normal speed in the BIOS, and it's back to running at a more comfortable 70C. Something funny's going on here.

Yes, the heatsink is hot, heat is transferring correctly. The fan is working fine, hot air is blowing off it. The problem is the CPU is creating way too much heat. Faulty CPU? Faulty motherboard? Anything I can do apart from just replacing one or the other? The CPU is an i5 3570K and has been run flat out for years (BOINC).

The BIOS won't let me lower the speed any more. I've reduced the base clock from 100 to 95, it won't go lower than that. It ignores me when I lower the multiplier (which is odd as it's a K CPU which should be unlocked?) But I have managed to disable the turbo function, so it doesn't jump up to 38 multiplier. So I've ended up with a 3.2GHz CPU instead of 3.8GHz.

 

[CompuTronix]

I have read about the TIM they're putting into newer CPUs (just to save a bit of money?!), and I agree that may be the problem. That would explain the gradual higher temperature. I can easily try a better cooler, but how do I take the CPU apart to change the internal compound? I didn't even think that was possible! Since I can by a used i5 3570K for £40, it's not worth spending much trying to repair it.

You can safely delid by using a "delidding tool" such as the Rockit 88 - https://rockitcool.myshopify.com/

If you prefer to have your 3570K professionally delidded, then just send it to Silicon Lottery - https://siliconlottery.com/collections/all/products/delid - which is a reputable company that tests, bins and sells overclocked, delidded "K" CPU's. The details are on their website. They do a perfect job.

CT

 

[hucker]

So the delidding tool costs almost as much as the 2nd hand value of the CPU. I don't think I'll bother! Presumably I can continue to use this CPU at a lower power (slower clock or less tasks running at once). If it eventually becomes unusable, I can buy a 2nd hand identical CPU, or just upgrade. In the meantime I might aswell try a better cooler.

 

[The Original Ralph]

nice insight on the TIM issue CompuTronix - i'd completely forgotten about that, and one of the reasons i went with the 5960x was they used an epoxy solder - i swear i've forgotten far more than i've retained

 

[CompuTronix]

... I can continue to use this CPU at a lower power ...

You can also experiment with decreasing Maximum Power State in Power Options, Advanced Settings, Processor Power Management. You might try setting it to about 75%. If you can dial in a setting where the Core temperatures don't exceed 85°C you'll be OK.

Here's the operating range for Core temperature:

Core temperatures above 85°C aren't recommended.

Core temperatures increase and decrease with Ambient temperature.

If you'd like to learn more about this topic, then you might want to read this: Intel Temperature Guide - http://www.tomshardware.com/forum/id-1800828/intel-temperature-guide.html

CT

 

[hucker]

... I can continue to use this CPU at a lower power ...

You can also experiment with decreasing Maximum Power State in Power Options, Advanced Settings, Processor Power Management. You might try setting it to about 75%. If you can dial in a setting where the Core temperatures don't exceed 85°C you'll be OK.

Is this a BIOS setting? Mine has nothing like that. There's a place I can set maximum watts (but it only applies to turbo mode).

 

[CompuTronix]

This is a Windows setting in Control Panel.

Click on Control Panel, Power Options, then to the right of the selected plan, click on Change plan setting. Next, click on Change advanced power settings, then drag the scroll bar down. Click on + next to Processor power management, then click on + next to Maximum processor state. This Setting can be changed, similar to Minimum power state as shown below. Set it to 75% and click Apply.

 

[hucker]

This is a Windows setting in Control Panel.

Click on Control Panel, Power Options, then to the right of the selected plan, click on Change plan setting. Next, click on Change advanced power settings, then drag the scroll bar down. Click on + next to Processor power management, then click on + next to Maximum processor state. This Setting can be changed, similar to Minimum power state as shown below. Set it to 75% and click Apply.

Brilliant! That provides an immediate effect and changes the temperature instantly with no rebooting. I also changed minimum state right down to 10% (I don't see why that needs to be high, it was at 90%?! - and it was also preventing the maximum from taking effect). What's odd though is that 100% to 90% changes about 10C instantly, but lowering it further doesn't alter the temperature so dramatically.