I am currently running my system at 90% cpu usage and 90% of cpus. CPU temps stay in the mid 60's or low 70s. I occasionally get that 80C spike but only when I try to run other programs and things at the same time.

As I said before, your CPU is spec'd to handle up to 100C. The occasional 80C is <well> within spec.

But it isn't good, especially so when the CPU is hardly doing any work at the time. And Just because you can do something doesn't mean you should. Just because a CPU is rated for a maximum temperature of 100°c doesn't mean you want it to reach that temperature.
Generally most electronics will run for decades 24/7 if it's temperature is 70°c or lower. When you get up around 80°c it's life expectancy reduces significantly. High 80°s and above, start saving for a replacement.

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Grant
Darwin NT

Yeah I agree with Grant here, the TJ max is 100C that is when it starts to throttle probably and running them at 90-100C will definitely kill my cpu much earlier.

However, your thoughts about running the CPU at 100% but using less CPUs is interesting, I did not know that the switching off and on would do damage? That is odd... And I tried it last night though, but my temps went back into the 80sC only running it at 30% of cpus but 100% usage. That's not good. The switching off and on actually might be good to keep the cpu cooler. So it seems either death by heat or death by switching... I don't know what is worse.

And yes, air cooling it seems not to be the right way, I just hesitate to install a water cooler, 1 cost and 2 leakage.

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I am currently running my system at 90% cpu usage and 90% of cpus. CPU temps stay in the mid 60's or low 70s. I occasionally get that 80C spike but only when I try to run other programs and things at the same time.

As I said before, your CPU is spec'd to handle up to 100C. The occasional 80C is <well> within spec.

But it isn't good, especially so when the CPU is hardly doing any work at the time. And Just because you can do something doesn't mean you should. Just because a CPU is rated for a maximum temperature of 100°c doesn't mean you want it to reach that temperature.
Generally most electronics will run for decades 24/7 if it's temperature is 70°c or lower. When you get up around 80°c it's life expectancy reduces significantly. High 80°s and above, start saving for a replacement.

Maybe so, but that's not what Jeff said (above) and you've way exaggerated what I replied, to the point of being unrelated to it

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However, your thoughts about running the CPU at 100% but using less CPUs is interesting, I did not know that the switching off and on would do damage? That is odd... And I tried it last night though, but my temps went back into the 80sC only running it at 30% of cpus but 100% usage. That's not good. The switching off and on actually might be good to keep the cpu cooler. So it seems either death by heat or death by switching... I don't know what is worse.

Ugh, that's not good. You definitely reduced CPUs as well, because (at least) 1 core less running really shouldn't end up increasing temps? I'm surprised.
Sounds like you had it right the first time. Ignore what I said then - it was only a side-point anyway

And yes, air cooling it seems not to be the right way, I just hesitate to install a water cooler, 1 cost and 2 leakage.

Cost, certainly yes (though with the amount you've spent on case fans... I digress).
Leakage: I've heard stories too - and they put me off originally - but I reckon those stories are apocryphal.
I mean, I might believe it with a custom kit where you have to fit everything together yourself and fill it with coolant etc. Anything might happen. I'm not suggesting that.
But these fully pre-built All-in-One's - not a chance unless you go at it with a hacksaw or chisel. And even then it'll take a while.
You're 10x more likely to damage fins on an air cooler, accidentally drop it on the CPU or misalign it while fitting due to the comical mismatch of size between the two, not to mention the restricted airflow it causes in the case.

The guy I used to use to build/upgrade my PCs about 8yrs ago asked me why I was wasting my time upgrading an aircooler (my first time) and told me about an AIO - "fit it and forget it". I was as reluctant then as you are now, having read the scare stories. I took his advice quite anxiously and ordered one for him to fit, but when I saw it (before even using it) I was almost embarrassed about how much time I'd wasted before going this route.
The chance of it leaking is <zero> imo and the only reason I replaced one was after I switched from a single 120mm to a double 140mm when I recased my whole PC. You'll never go back.
Ok, I'll stop now. That's my last effort

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