[SOLVED] Why is my Intel i5-8400 so hot?

Apr 30, 2020
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I just got a new intel i5 8400 and replaced it for my old i3 8100. But when I'm playing games like Overwatch and Rainbow Six Siege, my CPU temp goes up to the high 90s and my games keep crashing.
Is this just a bug in the MSI afterburner, or is the stock cooler not sufficient enough?
 
Solution
The stock cooler design is based on the average TDP of that class of cpu. TDP is calculated at base speeds with average use apps, that means no turbo or boost or hyperthreading and no extreme apps like gaming. It's generally recommended the cooler be capable of at least 1.5x the cpu TDP, with a preference for 2x TDP if you want silent ish performance at gaming use.

The i5-8400 is a 65w TDP cpu. It's best match is a decent 140w cooler, in the CM hyper212, Arctic esports 33/34 class of coolers. That'll keep gaming temps in the mid 50's usually.

The Intel stock cooler on that cpu is rated closer to @ 70w, it's good enough to keep average websurfing, Facebook or light gaming inside safe limits, but extreme usage like heavy gaming...
I just got a new intel i5 8400 and replaced it for my old i3 8100. But when I'm playing games like Overwatch and Rainbow Six Siege, my CPU temp goes up to the high 90s and my games keep crashing.
Is this just a bug in the MSI afterburner, or is the stock cooler not sufficient enough?
Probably a botched cooler installation, you'll have to get new thermal paste, remove the cooler, and apply it again, with a fresh thermal paste application. Try to make sure the cooler is seated properly. Once locked in, it should not be able to move at all, in any direction.
 
Apr 30, 2020
11
0
10
Probably a botched cooler installation, you'll have to get new thermal paste, remove the cooler, and apply it again, with a fresh thermal paste application. Try to make sure the cooler is seated properly. Once locked in, it should not be able to move at all, in any direction.
when I try to move the cooler, it doesn't budge at all, so I don't think its a botched installation
 
Apr 30, 2020
11
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It's the push-pin cooler, right? Those are easy to screw up. Did you install the pins diagonally, 2 at at time, and they CLICKED - they have to make that audible click.
Yeah it's the push pin, so what you're saying is that it should be sufficient to cool the cpu, it's just not installed properly?
 

Phaaze88

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Yeah it's the push pin, so what you're saying is that it should be sufficient to cool the cpu, it's just not installed properly?
That, and one other thing: What is the chassis?
The new cpu has more cores, clocks a little higher... it goes without saying that it's going to generate a little more heat.
You likely need to crank the case fans a little faster.
 

Karadjgne

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Ambassador
The stock cooler design is based on the average TDP of that class of cpu. TDP is calculated at base speeds with average use apps, that means no turbo or boost or hyperthreading and no extreme apps like gaming. It's generally recommended the cooler be capable of at least 1.5x the cpu TDP, with a preference for 2x TDP if you want silent ish performance at gaming use.

The i5-8400 is a 65w TDP cpu. It's best match is a decent 140w cooler, in the CM hyper212, Arctic esports 33/34 class of coolers. That'll keep gaming temps in the mid 50's usually.

The Intel stock cooler on that cpu is rated closer to @ 70w, it's good enough to keep average websurfing, Facebook or light gaming inside safe limits, but extreme usage like heavy gaming, rendering etc will put it to almost throttle/shutdown temps. Technically it passes, but realistically it sux, it's hot and loud and continuous extended periods of time at those temps will eventually shorten its useful lifespan.

Oh, and if you haven't already, go into bios and hit F5 to return bios back to factory optimized default settings (fix ram after). There's hidden settings in bios and sometimes they'll not change with a cpu swap. Resetting bios will optimize them for the i5-8400 and remove the prior i3-8100 settings.
 
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Solution
When the 8400 was first released, Hardware Unboxed reported it's included cooler was only barely adequate to keep temps at 90-95C under moderately heavy loads....and that heavy loads such as Blender, Cinebench, etc., actually led to thermal throttling...

I'd get another cooler....
 
Apr 30, 2020
11
0
10
The stock cooler design is based on the average TDP of that class of cpu. TDP is calculated at base speeds with average use apps, that means no turbo or boost or hyperthreading and no extreme apps like gaming. It's generally recommended the cooler be capable of at least 1.5x the cpu TDP, with a preference for 2x TDP if you want silent ish performance at gaming use.

The i5-8400 is a 65w TDP cpu. It's best match is a decent 140w cooler, in the CM hyper212, Arctic esports 33/34 class of coolers. That'll keep gaming temps in the mid 50's usually.

The Intel stock cooler on that cpu is rated closer to @ 70w, it's good enough to keep average websurfing, Facebook or light gaming inside safe limits, but extreme usage like heavy gaming, rendering etc will put it to almost throttle/shutdown temps. Technically it passes, but realistically it sux, it's hot and loud and continuous extended periods of time at those temps will eventually shorten its useful lifespan.

Oh, and if you haven't already, go into bios and hit F5 to return bios back to factory optimized default settings (fix ram after). There's hidden settings in bios and sometimes they'll not change with a cpu swap. Resetting bios will optimize them for the i5-8400 and remove the prior i3-8100 settings.
ok thanks, I'll look into getting the CM hyper212 cooler. But the weirdest thing is that sometimes the temps go to mid to high 90º, and sometimes the temp stays at a low 70º. And temp often changes by almost 10º a second
 
I forgot to add that in the same game the temps are either high 90º or low 70º
That's still possible, some areas can be more CPU demanding than others, if you really want to compare you need to be in the same game, same area, try to have similar AI, make sure the same background apps are running both times, nothing going on in the background, roughly similar ambient temps, etc. The same game can have different CPU temps due to way too many reasons, but if your CPU is hitting 90+ C, you need to look into it no matter what.