8700 getting hot in small case under stress test

[slippyjim]

I have the folloiwng
i7 8700
HyperX ddr4 @3000MHz
Asus Z370-E
MSI Aero 1080Ti
Noctua nh-l9i cooler

Its a very tight small case with not great ventilation but that can not be improved further, the only thing that might help is a small form factor PSU that is powerful enough as that might enable me to fit a bigger fan onto the CPU heatsink but I can't do that right now.

With Multi core enhancement set to Auto in BIOS
I run Prime95 v26.6 Blend and HWMonitor says each core is at 4300 or 4400MHz and each core is at 100C I have also opened Intel XTU & it says it is being thermally throttled. Is this ok or will it damage the CPU long term? Should I restrict the max boost speed for each core in BIOS?

With Multi core enhancement set to Disabled in BIOS
I run Prime95 v26.6 Blend and HWMonitor says each core is at 1800MHz and each core is around 73C I have also opened Intel XTU & it says it is being power throttled.

Thanks

 

[jay32267]

Have you considered moving everything to a bigger case?

as you said "with not great ventilation but that can not be improved further"

It seems you aren't going to get the full use of you 8700 the way you are now.

 

[bmockeg]

Well,
1. Even in the BEST ventilated case, the 8700 stock cooler is insufficient. Buying a new power supply or case won't solve the issue. My recommendation is get a 120mm AIO water cooler.

 

[Supernova1138]

Well,
1. Even in the BEST ventilated case, the 8700 stock cooler is insufficient. Buying a new power supply or case won't solve the issue. My recommendation is get a 120mm AIO water cooler.

He's not using the stock cooler but is using an aftermarket heatsink that probably isn't too much better. The 8700 runs hot unless you disable TurboBoost and let it run at the 3.2GHz base clock, taking a rather large performance hit. Basically you need a larger cooler, and that may mean a larger case if the best aftermarket cooler you can fit is the Noctua NH-L9I. A 120mm AIO might be the only option without a case swap, assuming this case has a 120mm fan slot that the radiator can be attached to.

 

[bmockeg]

I see, if the noctua isn't working then an AIO is probably the only option

 

[slippyjim]

I can not use a different case, its a custom 3 screen portable PC
The Noctua fan is the best fan for the situation as I have very limited height available

If I set the RAM to XMP 3000 then the CPU gets thermally throttled, sometime it was at 100C another at around 97C, it seemed to depend how much it put VCore upto, sometimes it was 1.216 others just over 1.3

I reset BIOS to default and so the RAM was just at stock 2400MHz then ran Prime95 and the CPU was power throttled, VCore actually went down to 1V

I thought XMP only affected the RAM settings not the CPU as well

Is this how the XMP and boost work? It seems a bit weird to me

 

[bmockeg]

Well it's just going to thermal throttle then, that's how it is

 

[mdd1963]

Certainly turning off MCE (especially in a small cramped case) will spare you the heat caused by all cores attempting to potentially turbo to max clock speeds, possibly sparing you several degrees...(A GTX1080Ti in a smallish/cramped case can't be helping, to be sure)

 

[mdd1963]

I'd certainly try a $50-$60 Corsair100R midtower case, which has clearance for any cooler up to the Noctua NH-D15...(I have on in mine, still a fairly medium-small mid-tower, and near dead-quiet, as I had to look to see if it had powered up even with the windowed side-cover removed during initial power on); if you are going to be running at near 8700K specs, you can likely expect 'near 8700K' heat...

 

[R4DIO4CT1VE]

Under normal use does it thermal throttle? if not, than its not really a problem.

 

[smartauthentification]

You can maybe upgrade the cooler, or add some fans. Or if it isn't getting hotter than 85C you're good.

 

[slippyjim]

I cant change the case as its a case with built in screens, its a funky "portable" pc

Prime 95 gets it up to 100C even with boost disabled

Turning off MCE to put it bluntly fucks things up, it reduces the Vcore and then the CPU gets power throttled

Just gonna have to see what its like under normal work load and take it from there

 

[bmockeg]

Prime 95 is completely different than normal workload. You may never het the CPU that high.

 

[slippyjim]

Yeah thats what I'm hoping, its going to be used for VR development but probably not all cores maxed out so hopefully be fine