4790k Idling at 40C, jumps to 99C in Prime95 with H100i AIO

[zahnib]

Hey guys. So I've just installed a Corsair H100i onto my 4790K. I previously had a Corsair H75 on there but wanted a bit of an upgrade.

Seeing as it was my first time installing a cooler I wanted to make sure all the temps were okay and everything was running smoothly. I should have done this before taking my old cooler off so I had a point of reference, but alas I did not.
After installing the H100i I used CoreTemp to see how my idle temperatures were, they sat between 35-40ºC. This seemed a little high to me but after digging around on the internet it seemed like this was not uncommon, but also other people were getting temps 10 degrees lower with a similar setup, so something wasn't right. My CPU wasn't overclocked at all.

Idle temperatures

I then moved onto stress testing. Prime95 came up as a good free stress test so I ran the SmallFFTs. Strait away my temps jumped up to 98-100ºC!! What the flip is going on!!
So I removed the cooler, reapplied the thermal compound (CoolerMaster Mastergel, not the best I know but should suffice), I made sure the thumb screws connecting the cooler to the standoffs where tight and that everything was plugged in (fans, etc.). Ran the test again but temps hadn't changed.

During SmallFFTs

I'd read somewhere that changing the fans to 'Performance Mode' in Corsair Link could help, so tried this out but no change.

Corsair Link readout at idle

So what do you guys think?

 

[chemmajorp53]

Can you hear the pump running and are you 100% sure that the block is making adequate contact with the CPU?

 

[zahnib]

Can you hear the pump running and are you 100% sure that the block is making adequate contact with the CPU?

The block is definitely in contact with the CPU. I'm not sure what the pump is supposed to sound like, is it an audible gurgling noise or something similar?

 

[chemmajorp53]

It's like a low humming noise, if you hear distinct gurgling or metal on metal contact then return it because there's probably some air in the pump. If you don't hear anything then it's either not hooked up correctly or the pump is faulty

 

[zahnib]

There is a low hum but its hard to distinguish from the fans, when I get home I'll disconnect the fans and see if I can still hear it

 

[zahnib]

Okay I checked the pump without the fans. I can't really hear anything, I plugged in my old H75 for comparison and with that you can definitely hear fluid moving.
I left my computer running and unplugged the SATA power connector for the H100i and temps immediately started to rise, this would suggest to me that the pump is working in some form?

Also I thought I'd try out a real world test so fired up Tomb Raider (2013) and ran the benchmark on Ultimate. Temperatures stayed below 50ºC for the whole thing and I averaged at 60fps

 

[zahnib]

Okay so after a bit more digging it sounds like Prime95 might be part of the problem. Versions after 26.6 seem to generate unrealistically high temperatures. I managed to find an installer for version 26.6 and was able to run SmallFFTs with temperatures hovering between 70ºC and 80ºC.

So maybe not quite so much reason for concern. The fact that my idle temps are still at the high end of the spectrum is a bit puzzling though

 

[kol12]

Is it quite warm ie: summer where you are? What does the first pic of LINK represent, and idle state or a game or benchmark?

39C on the 1070 is a high idle, it would have to very warm where you are for an idle temp like that. Cpu temps are high too if they are idle temps...

Need more details about what state the computer was in when you took the screenshot of LINK...

 

[zahnib]

Is it quite warm ie: summer where you are? What does the first pic of LINK represent, and idle state or a game or benchmark?

39C on the 1070 is a high idle, it would have to very warm where you are for an idle temp like that. Cpu temps are high too if they are idle temps...

Need more details about what state the computer was in when you took the screenshot of LINK...

My bad, yes the Corsair Link readout is at idle. My ambient room temps were not excessively high, I live in Australia but it is the start of Autumn so the room temp would have been around 25ºC. Humidity has been quite high however, plus I do have a small case (Corsair 250D).

 

[kol12]

Hmm, your gaming temps seem good, under 50C? I live in NZ so temperatures are sort of similar depending on where in AU you are? The coolant temp at 33.5C is what I would expect for an ambient of 25C maybe a little less, but you mention high humidity also. I think your idle cpu temps are too high for this cooler and don't reflect the other temperatures mentioned above. Are you sure there was nothing using the cpu at a moderate level while you took the screen shot? I have to ask the same for the gpu as well because a 1070 should not idle at 39C. What is the fan setup in your 250D?

 

[zahnib]

Hmm, your gaming temps seem good, under 50C? I live in NZ so temperatures are sort of similar depending on where in AU you are? The coolant temp at 33.5C is what I would expect for an ambient of 25C maybe a little less, but you mention high humidity also. I think your idle cpu temps are too high for this cooler and don't reflect the other temperatures mentioned above. Are you sure there was nothing using the cpu at a moderate level while you took the screen shot? I have to ask the same for the gpu as well because a 1070 should not idle at 39C. What is the fan setup in your 250D?

Took measurements again, below screen shot is system at idle after about 30 minutes, ambient room temperature is approximately 24ºC and humidity is 46%.

Fan set up is one 140mm fan pulling air into the case at the front, two 120mm fan on the rad pushing air out of the case on the side and the GPU doing whatever it does on the other side (can't remember if it pushes or pulls)

 

[kol12]

You might run a few degrees higher with this case compared to a larger case. The water temp (29.5) matches the ambient temp and probably the design of the case but the idle cpu temps still seem a little bit high, this could be related to air flow in the case but it could also be the thermal compound you used as I note you have been taking the cooler on and off. Did you clean both the cpu and cooling plate with alcohol? Did you apply the correct amount of thermal compound? You may need some better TIM. What are your gaming temps right now?

I'm still a little concerned about the idle temp of your GTX 1070, I've read that the gpu can run a fraction warmer in the 250D than larger cases but it still seems quite high. Considering the ambient temp you have and lesser airflow of the 250D it could be normal. What are the gpu gaming temps? Usually the ssd temp would be higher than what you have also, where is the ssd located?

I suggest you try OCCT for stress testing, it's better than Prime95. Check it out here: http://www.ocbase.com/

 

[zahnib]

You might run a few degrees higher with this case compared to a larger case. The water temp (29.5) matches the ambient temp and probably the design of the case but the idle cpu temps still seem a little bit high, this could be related to air flow in the case but it could also be the thermal compound you used as I note you have been taking the cooler on and off. Did you clean both the cpu and cooling plate with alcohol? Did you apply the correct amount of thermal compound? You may need some better TIM. What are your gaming temps right now?

I'm still a little concerned about the idle temp of your GTX 1070, I've read that the gpu can run a fraction warmer in the 250D than larger cases but it still seems quite high. Considering the ambient temp you have and lesser airflow of the 250D it could be normal. What are the gpu gaming temps? Usually the ssd temp would be higher than what you have also, where is the ssd located?

I suggest you try OCCT for stress testing, it's better than Prime95. Check it out here: http://www.ocbase.com/

The case size I think could definitely be pushing temps up a little. The thermal compound I'm using (CoolerMaster Mastergel) has lower thermal properties than some other compounds so might be something I need to look at as well. I've been cleaning the CPU and cooling plate each time I've reapplied compound. I've just been squeezing a small sausage onto the CPU and then pressing the cooling plate onto it and giving it a bit of a twist to spread it about.

I've only run the Tomb Raider (2013) benchmark as far as gaming goes. With settings at ultimate the CPU didn't go above 50°C, I didn't think to check the GPU temp though. I'll check this out when I get home. I have run FurMark on the GPU to check its stability though and it was fine over a prolonged period.

The SSD is located in a drive cage below the motherboard so pretty well isolated from the rest of the system.

I did actually run some stress test using OCCT. This really pushed my CPUs temps up and on the small data set mode it pushed my CPU above its threshold (85°C I think). It remained stable over a prolonged period on the large data set however.

 

[zahnib]

Okay so turns out my 1070 is one of the cards effected by heat issues. I've updated the BIOS (at current it is running 35ºC idle, though ambient temperature is also about 4ºC lower) and ordered the thermal mod kit form EVGA. I've also ordered another tube of thermal paste; Noctua NT-H1 - from what I've read it seems like a pretty solid performer so we'll see how it compares to the CoolerMaster stuff.

I ran OCCT's small data set again and it lasted just over 30 minutes before core #0 one t above 85ºC and needed the test.

In the mean time I've done a bit of cable management to try and increase general air flow, as well as just making things look nice 😉

 

[junkeymonkey]

you do see a lot of posts on that cooler and like ones

http://www.tomshardware.com/forum/all.html?refine=h100i+hot

http://www.tomshardware.com/forum/all.html?refine=h100i+temps

my cheap 25$ air cooler does a better job [opinion]

 

[kol12]

Okay so turns out my 1070 is one of the cards effected by heat issues. I've updated the BIOS (at current it is running 35ºC idle, though ambient temperature is also about 4ºC lower) and ordered the thermal mod kit form EVGA. I've also ordered another tube of thermal paste; Noctua NT-H1 - from what I've read it seems like a pretty solid performer so we'll see how it compares to the CoolerMaster stuff.

I ran OCCT's small data set again and it lasted just over 30 minutes before core #0 one t above 85ºC and needed the test.

In the mean time I've done a bit of cable management to try and increase general air flow, as well as just making things look nice 😉

That makes sense then, (the 1070 temps). I got my 1070 from a "fixed" batch so didn't face that issue. The thermal mod kit should knock temps back further. Could be a bit of pain to install though...

The cpu idle temps are still higher than I would expect with the current coolant temperature. The only thing I can think of is a poor connection between the cooling plate and the cpu or a bad application of thermal compound. Inadequate airflow would make the coolant temp as well as the cpu temps increase.

How much voltage are you running to the 4790k? Is your power plan on balanced or performance? Do you have Intel speedstep enabled? Any of these could raise cpu temps as well...

The small data set in OCCT is designed to obtain maximum heat, you want to test for stability if you are overclocking and the large data set would be better for that...

Another good test that is less demanding than OCCT is Intel XTU. Check it out here: https://downloadcenter.intel.com/download/24075/Intel-Extreme-Tuning-Utility-Intel-XTU-

 

[zahnib]

you do see a lot of posts on that cooler and like ones

http://www.tomshardware.com/forum/all.html?refine=h100i+hot

http://www.tomshardware.com/forum/all.html?refine=h100i+temps

my cheap 25$ air cooler does a better job [opinion]

Yeah looks like quite a few others are having problems, but their are loads of people that are really happy with it too so who knows. I like the design and at the end of the day gaming temps are pretty good.

That makes sense then, (the 1070 temps). I got my 1070 from a "fixed" batch so didn't face that issue. The thermal mod kit should knock temps back further. Could be a bit of pain to install though...

The cpu idle temps are still higher than I would expect with the current coolant temperature. The only thing I can think of is a poor connection between the cooling plate and the cpu or a bad application of thermal compound. Inadequate airflow would make the coolant temp as well as the cpu temps increase.

How much voltage are you running to the 4790k? Is your power plan on balanced or performance? Do you have Intel speedstep enabled? Any of these could raise cpu temps as well...

The small data set in OCCT is designed to obtain maximum heat, you want to test for stability if you are overclocking and the large data set would be better for that...

Another good test that is less demanding than OCCT is Intel XTU. Check it out here: https://downloadcenter.intel.com/download/24075/Intel-Extreme-Tuning-Utility-Intel-XTU-

I'll try out the Noctua paste when it arrives so if I've done a bad application hopefully that'll sort it out.

I'm running the 4790k at stock at the moment. SpeedStep is enabled - I'll put a screen from HardwareMonitor down below for you

 

[kol12]

Why is the Cpu at max frequency (4397 MHz) in that shot? Is your power plan on performance or balanced?

 

[zahnib]

Why is the Cpu at max frequency (4397 MHz) in that shot? Is your power plan on performance or balanced?

Set to performance. Initially I'd read that would increase cooling but now that I think of it that might also explain some of the heat?

I'm thinking this all might not be such a problem, I haven't encountered any problems so far, it seems that temperatures stay in an acceptable range during real world load (gaming and such) so its really just the idles that are hit odd.

 

[kol12]

Why is the Cpu at max frequency (4397 MHz) in that shot? Is your power plan on performance or balanced?

Set to performance. Initially I'd read that would increase cooling but now that I think of it that might also explain some of the heat?

I'm thinking this all might not be such a problem, I haven't encountered any problems so far, it seems that temperatures stay in an acceptable range during real world load (gaming and such) so its really just the idles that are hit odd.

Performance mode is going to override SpeedStep which is your power saving feature, only enable performance mode if you think you'll need it. This probably explains your high idle temps, in performance mode the voltage and core clock remains constant at maximum. SpeedStep allows the CPU to adjust (lower) both voltage and core clock speed based on the CPU load, this in turn saves power. I don't usually even need to switch to performance mode, if a game requires maximum voltage and clock speed it will ask for and get it in balanced mode.

What are your current idle and gaming temps? Can you switch to balanced power mode and report back with the temps? I create a shortcut to power options on the desktop so I can easily switch between balanced and performance if I want to.

The 25C ambient temp you had the other day is enough to cause a high idle temp. I have air conditioning in my room and if it is not on I've had similar ambient temps over the summer. At 24-25C the CPU can idle at about 35C+, my 1070 will idle at about 35-37C also.

 

[zahnib]

Why is the Cpu at max frequency (4397 MHz) in that shot? Is your power plan on performance or balanced?

Set to performance. Initially I'd read that would increase cooling but now that I think of it that might also explain some of the heat?

I'm thinking this all might not be such a problem, I haven't encountered any problems so far, it seems that temperatures stay in an acceptable range during real world load (gaming and such) so its really just the idles that are hit odd.

Performance mode is going to override SpeedStep which is your power saving feature, only enable performance mode if you think you'll need it. This probably explains your high idle temps, in performance mode the voltage and core clock remains constant at maximum. SpeedStep allows the CPU to adjust (lower) both voltage and core clock speed based on the CPU load, this in turn saves power. I don't usually even need to switch to performance mode, if a game requires maximum voltage and clock speed it will ask for and get it in balanced mode.

What are your current idle and gaming temps? Can you switch to balanced power mode and report back with the temps? I create a shortcut to power options on the desktop so I can easily switch between balanced and performance if I want to.

The 25C ambient temp you had the other day is enough to cause a high idle temp. I have air conditioning in my room and if it is not on I've had similar ambient temps over the summer. At 24-25C the CPU can idle at about 35C+, my 1070 will idle at about 35-37C also.

I think you might be right. Things seem pretty stable now. Thanks everyone for your help!

 

[kol12]

I think you might be right. Things seem pretty stable now. Thanks everyone for your help!

That's great! It sounds like things are sorted. What are temps like in balanced mode?