Question CPU running hot for no reason - need help with fan layout

Kvnnon

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So my Ryzen 5 3600 is running super hot at idle lately. Between 50 and 70 degrees Celsius is where it's at. I have a Cooler Master ML240R aio, with two fans at the front with the rad as intake, the back fan as intake and two top fans as exhaust. I have no clue why it's so hot and need some advice. My case is the Thermaltake J25 RGB. Thanks
 
Your pump is not running. That's the only way you'd get 50-70 degree temperatures unless the water block isn't properly mounted to the motherboard. Chances are about 95% that your pump has failed OR you have an air lock in the loop.

Try tilting the case front to back on it's edges and side to side as well, slowly, to try and dislodge the air bubble. The goal is to try and get the radiator higher than the water block so that the air bubble tends to move along to the radiator where it belongs and away from the pump and water block.

If that fails to help things, then I'd contact Cooler master about a warranty replacement OR purchase a new cooler.

Also, just to verify function, going into the BIOS to verify that there is an adequate RPM signal on the fan header your pump is attached to is a good idea as well.
 

Kvnnon

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Thanks for your reply
I'm not very educated on this front, but in MSI Dragon Centre it says the pump is running at 2300rpm. It also says the system fans are not running, but that is clearly a glitch as they are obviously running. I only bought the aio around a week ago, and the radiator is higher than the air block. I am not sure what is happening, would really appreciate some more advice.
 
With the unit running, tilt the case backwards until it is ALMOST having to lay on the cords, then tilt it slowly side to side. See if you can't get the air bubble to let loose and flow to the radiator. I'm almost certain you have an air bubble causing a vapor lock.

I'll be honest though, Cooler master is far from the best brand to purchase an AIO from. If you can't get it sorted out pretty soon, then stop running it and get a different cooler or contact CM. You do not want to risk damaging your CPU by continuing to run it under poor cooling conditions.
 

Kvnnon

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With the unit running, tilt the case backwards until it is ALMOST having to lay on the cords, then tilt it slowly side to side. See if you can't get the air bubble to let loose and flow to the radiator. I'm almost certain you have an air bubble causing a vapor lock.

I'll be honest though, Cooler master is far from the best brand to purchase an AIO from. If you can't get it sorted out pretty soon, then stop running it and get a different cooler or contact CM. You do not want to risk damaging your CPU by continuing to run it under poor cooling conditions.
How are you sure it's an air bubble? Also is there a chance that its the fan arrangement/ poor airflow in the case? I was getting similar temperatures with the stock Ryzen cooler.
 
Even without any fans at ALL, any 240mm or larger AIO with a pump that is functioning should easily be able to keep IDLE temperatures below 50°C. That is how I know, or at least greatly suspect, that it is a pump issue. Also, because I've seen this about four thousand times. Yes, it could ALWAYS be something else, but you start there and then work your way to other issues.

If it was a fan problem, then you'd know because the fans wouldn't be running. If you THINK maybe it has to do with OTHER fans, take the side panel off, see if it makes any difference. It won't, not in this case, but it's worth trying anyhow.
 

Kvnnon

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Even without any fans at ALL, any 240mm or larger AIO with a pump that is functioning should easily be able to keep IDLE temperatures below 50°C. That is how I know, or at least greatly suspect, that it is a pump issue. Also, because I've seen this about four thousand times. Yes, it could ALWAYS be something else, but you start there and then work your way to other issues.

If it was a fan problem, then you'd know because the fans wouldn't be running. If you THINK maybe it has to do with OTHER fans, take the side panel off, see if it makes any difference. It won't, not in this case, but it's worth trying anyhow.
Well after running some tests, the computer runs at around 60-70 degrees Celsius under load, whereas without the aio it would easily get to 90-100. Is it possible that the aio is in fact doing its job and I am just in a hot room?
 
Well after running some tests, the computer runs at around 60-70 degrees Celsius under load

What tests? What kind of load? A gaming load? A utilty that tests CPU and memory, but does not provide a steady-state load that is 100% of TDP? Or a fully steady state 100% load like what is found using Prime95 Small FFT or OCCT small data set, with AVX and AVX2 disabled?

If your tests were done using an acceptable and recommended utility, for the purpose of thermal testing (Not one intended for stability testing, as testing stability and thermal compliance are two entirely different things), then a maximum temperature of 70°C is pretty good assuming it's not because it's actually being throttled due to exceeding specification.

So what exactly were you using to apply the load, and what were you using to monitor thermal response?

For this purpose I would recommend using ONLY Ryzen master, HWinfo or Core Temp.

Monitoring software

HWmonitor, Open hardware monitor, Realtemp, Speccy, Speedfan, Windows utilities, CPU-Z, NZXT CAM and most of the bundled motherboard utilities are often not the best choice as they are not always accurate. Some are actually grossly inaccurate, especially with certain chipsets or specific sensors that for whatever reason they tend to not like or work well with. I've found HWinfo or CoreTemp to be the MOST accurate with the broadest range of chipsets and sensors. They are also almost religiously kept up to date.

CoreTemp is great for just CPU thermals including core temps or distance to TJmax on older AMD platforms.

HWinfo is great for pretty much EVERYTHING, including CPU thermals, core loads, core temps, package temps, GPU sensors, HDD and SSD sensors, motherboard chipset and VRM sensor, all of it. When starting HWinfo after installation, always check the box next to "sensors only" and de-select the box next to "summary".


Run HWinfo and look at system voltages and other sensor readings.

Monitoring temperatures, core speeds, voltages, clock ratios and other reported sensor data can often help to pick out an issue right off the bat. HWinfo is a good way to get that data and in my experience tends to be more accurate than some of the other utilities available. CPU-Z, GPU-Z and Core Temp all have their uses but HWinfo tends to have it all laid out in a more convenient fashion so you can usually see what one sensor is reporting while looking at another instead of having to flip through various tabs that have specific groupings, plus, it is extremely rare for HWinfo to not report the correct sensor values under the correct sensor listings, or misreport other information. Utilities like HWmonitor, Openhardware monitor and Speccy, tend to COMMONLY misreport sensor data, or not report it at all.

After installation, run the utility and when asked, choose "sensors only". The other window options have some use but in most cases everything you need will be located in the sensors window. If you're taking screenshots to post for troubleshooting, it will most likely require taking three screenshots and scrolling down the sensors window between screenshots in order to capture them all.

It is most helpful if you can take a series of HWinfo screenshots at idle, after a cold boot to the desktop. Open HWinfo and wait for all of the Windows startup processes to complete. Usually about four or five minutes should be plenty. Take screenshots of all the HWinfo sensors.

Next, run something demanding like Prime95 (With AVX and AVX2 disabled) or Heaven benchmark. Take another set of screenshots while either of those is running so we can see what the hardware is doing while under a load.


*Download HWinfo



For temperature monitoring only, I feel Core Temp is the most accurate and also offers a quick visual reference for core speed, load and CPU voltage:


*Download Core Temp




Ryzen master for Zen or newer AMD CPUs, or Overdrive for older Pre-Ryzen platforms (AM3/AM3+/FM2/FM2+)

For monitoring on AMD Ryzen and Threadripper platforms including Zen or newer architectures, it is recommended that you use Ryzen master if for no other reason than because any updates or changes to monitoring requirements are more likely to be implemented sooner, and properly, than with other monitoring utilities. Core Temp and HWinfo are still good, with this platform, but when changes to CPU micro code or other BIOS modifications occur, or there are driver or power plan changes, it sometimes takes a while before those get implemented by 3rd party utilities, while Ryzen master, being a direct AMD product, generally gets updated immediately. Since it is also specific to the hardware in question, it can be more accurately and specifically developed without any requirement for inclusion of other architectures which won't be compatible in any case. You wouldn't use a hammer to drive a wood screw in (At least I hope not) and this is very much the same, being the right tool for the job at hand.




*Download Ryzen Master




Also, posting screenshots, when requested, is helpful so WE can see what is going on as well and you can learn how to do that here:

How to post images on Tom's hardware forums

 

Kvnnon

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Feb 23, 2019
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What tests? What kind of load? A gaming load? A utilty that tests CPU and memory, but does not provide a steady-state load that is 100% of TDP? Or a fully steady state 100% load like what is found using Prime95 Small FFT or OCCT small data set, with AVX and AVX2 disabled?

If your tests were done using an acceptable and recommended utility, for the purpose of thermal testing (Not one intended for stability testing, as testing stability and thermal compliance are two entirely different things), then a maximum temperature of 70°C is pretty good assuming it's not because it's actually being throttled due to exceeding specification.

So what exactly were you using to apply the load, and what were you using to monitor thermal response?

For this purpose I would recommend using ONLY Ryzen master, HWinfo or Core Temp.

Monitoring software

HWmonitor, Open hardware monitor, Realtemp, Speccy, Speedfan, Windows utilities, CPU-Z, NZXT CAM and most of the bundled motherboard utilities are often not the best choice as they are not always accurate. Some are actually grossly inaccurate, especially with certain chipsets or specific sensors that for whatever reason they tend to not like or work well with. I've found HWinfo or CoreTemp to be the MOST accurate with the broadest range of chipsets and sensors. They are also almost religiously kept up to date.

CoreTemp is great for just CPU thermals including core temps or distance to TJmax on older AMD platforms.

HWinfo is great for pretty much EVERYTHING, including CPU thermals, core loads, core temps, package temps, GPU sensors, HDD and SSD sensors, motherboard chipset and VRM sensor, all of it. When starting HWinfo after installation, always check the box next to "sensors only" and de-select the box next to "summary".


Run HWinfo and look at system voltages and other sensor readings.

Monitoring temperatures, core speeds, voltages, clock ratios and other reported sensor data can often help to pick out an issue right off the bat. HWinfo is a good way to get that data and in my experience tends to be more accurate than some of the other utilities available. CPU-Z, GPU-Z and Core Temp all have their uses but HWinfo tends to have it all laid out in a more convenient fashion so you can usually see what one sensor is reporting while looking at another instead of having to flip through various tabs that have specific groupings, plus, it is extremely rare for HWinfo to not report the correct sensor values under the correct sensor listings, or misreport other information. Utilities like HWmonitor, Openhardware monitor and Speccy, tend to COMMONLY misreport sensor data, or not report it at all.

After installation, run the utility and when asked, choose "sensors only". The other window options have some use but in most cases everything you need will be located in the sensors window. If you're taking screenshots to post for troubleshooting, it will most likely require taking three screenshots and scrolling down the sensors window between screenshots in order to capture them all.

It is most helpful if you can take a series of HWinfo screenshots at idle, after a cold boot to the desktop. Open HWinfo and wait for all of the Windows startup processes to complete. Usually about four or five minutes should be plenty. Take screenshots of all the HWinfo sensors.

Next, run something demanding like Prime95 (With AVX and AVX2 disabled) or Heaven benchmark. Take another set of screenshots while either of those is running so we can see what the hardware is doing while under a load.


*Download HWinfo



For temperature monitoring only, I feel Core Temp is the most accurate and also offers a quick visual reference for core speed, load and CPU voltage:


*Download Core Temp




Ryzen master for Zen or newer AMD CPUs, or Overdrive for older Pre-Ryzen platforms (AM3/AM3+/FM2/FM2+)

For monitoring on AMD Ryzen and Threadripper platforms including Zen or newer architectures, it is recommended that you use Ryzen master if for no other reason than because any updates or changes to monitoring requirements are more likely to be implemented sooner, and properly, than with other monitoring utilities. Core Temp and HWinfo are still good, with this platform, but when changes to CPU micro code or other BIOS modifications occur, or there are driver or power plan changes, it sometimes takes a while before those get implemented by 3rd party utilities, while Ryzen master, being a direct AMD product, generally gets updated immediately. Since it is also specific to the hardware in question, it can be more accurately and specifically developed without any requirement for inclusion of other architectures which won't be compatible in any case. You wouldn't use a hammer to drive a wood screw in (At least I hope not) and this is very much the same, being the right tool for the job at hand.




*Download Ryzen Master




Also, posting screenshots, when requested, is helpful so WE can see what is going on as well and you can learn how to do that here:

How to post images on Tom's hardware forums

thanks so much for your help so far. It was a gaming load if you were still wondering. Also, I can all of a sudden hear liquid splashing around in the aio. Is this something to be worried about?
 

Kvnnon

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You can likely hear liquid splashing around because the pump is churning water and air, due to a bubble OR due to coolant loss in the loop. I'd contact Cooler Master ASAP.
The water sound is gone now. I'm not sure what it was about and it only lasted for a little bit. There is definitely no coolant loss or I would've noticed by now.
 
Coolant loss could happen before the cooler ever even leaves the warehouse or retailer. It can also happen so slowly that it completely evaporates before it is even appreciable to the eye, but over time can result in enough coolant loss to create an air bubble inside the loop.

If there is a lack of cooling performance, gurgling noises, or anything that is not directly related to fan performance, then there is a problem and the cooler should be replaced if it has already been determined that the problem is not related to the mounting of the water block or pump assembly, and that the thermal interface material is not to blame.
 

Kvnnon

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Coolant loss could happen before the cooler ever even leaves the warehouse or retailer. It can also happen so slowly that it completely evaporates before it is even appreciable to the eye, but over time can result in enough coolant loss to create an air bubble inside the loop.

If there is a lack of cooling performance, gurgling noises, or anything that is not directly related to fan performance, then there is a problem and the cooler should be replaced if it has already been determined that the problem is not related to the mounting of the water block or pump assembly, and that the thermal interface material is not to blame.
Thank you very much for your help. I think I will leave it be for the moment, if problems persist I will contact Cooler Master.
 
You're idling at 50-70°C and you're going to "leave it be" without verifying that it's not actually exceeding specifications? That's nuts. You're going to end up cooking your hardware, but that's your decision. Sure hope you're not out of warranty by the time you accept the fact that there's a problem.

Again, it's worth mentioning that it MIGHT be fine that you seem to have a high idle temperature but ONLY if your maximum temperature doesn't exceed 80°C and the only way to know that is to run the appropriate thermal tests to determine if it is thermally compliant or not. Either way, good luck.
 

Kvnnon

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You're idling at 50-70°C and you're going to "leave it be" without verifying that it's not actually exceeding specifications? That's nuts. You're going to end up cooking your hardware, but that's your decision. Sure hope you're not out of warranty by the time you accept the fact that there's a problem.

Again, it's worth mentioning that it MIGHT be fine that you seem to have a high idle temperature but ONLY if your maximum temperature doesn't exceed 80°C and the only way to know that is to run the appropriate thermal tests to determine if it is thermally compliant or not. Either way, good luck.
Quote possible I just be vibing in a hot room. It is the hottest room in the house and I didn't get these temps with my old pc with a stock ryzen cooler.
 

Kvnnon

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So basically we're just not willing to do the recommended testing to be sure one way or the other? Ok.
Well what is the recommended testing? What programs etc.? Also do you think it would make a difference if I had two fans at the top as intake, two at the front as intake and one at the back as exhaust?
 
No, that would be a completely wrong configuration. Top and rear fans should ALWAYS be exhaust, in 99.9% of configurations, and in 100% of tower case configurations, while front, bottom and side fans should always be configured as intake fans. Power supply, when bottom mounted, should, in about 99% of configurations, be facing it's intake grill down, not into the case, and be completely separate as far as airflow is concerned, from the rest of the internal case, and venting out the back.

So, for almost all cases, and pretty much ALL tower ATX cases, front intake, rear and top exhaust. On those few cases with side panel fan locations, those should also be intake. IF you can squeeze a fan into the bottom of the case, if there is a fan location there, that too should be intake, but it's rare that anybody can use those.


Testing thermal compliance

Once you get to the Windows desktop, the first thing you will want to do is open HWinfo (Sensors only option), Core Temp or Ryzen Master and take a look at what your core and package temperatures are doing. At idle your core temps should be somewhere below 40°C in the majority of cases. Preferably somewhere in the mid to low 30’s. On some newer very high core count models, or if you are using the stock cooler (In which case you shouldn't be overclocking anyhow), then it might not be below the 40°C threshold.

If you are not overclocking and are ONLY testing the thermal compliance of the stock configuration, then don't be TOO concerned by a high idle temperature UNLESS you also have a high load temperature that is outside of spec. This WILL be affected by whatever the ambient temperature is in the room where you are, so if your are in a very warm region and have no air conditioning going you may have an idle temp that is a bit closer to 40. For cooler ambient rooms or regions it will likely show low 30’s-ish. Be aware that unless you have excessively high idle temps, say, above 40°C, then what your actual idle temps are is practically irrelevant. Cooler idle temps are not indicative of much of anything specific.

Very HIGH idle temps however DO indicate that there is likely a problem with an incorrectly installed CPU cooler heatsink, too high of CPU core voltage or some other cooling or voltage related issue. If you are using one of those other utilities I warned about in the beginning of this tutorial, it may also be that the utility is reporting falsely. In that case, go get HWinfo or CoreTemp and check again.

If idle temps seem fine, then leave your monitoring application open and run Prime95 (Either version 26.6 or the latest version with AVX/AVX2 disabled).

Choose the Small FFT option (NOT "Smallest FFT") and allow it to run for fifteen minutes. If you are using the latest version of Prime95 (Version 29.8 or newer) then you NEED to be sure to disable the AVX and AVX2 options in the main options window. When you disable AVX2 the option to disable AVX will become available. If at any point your core or package temperatures exceed 80°C for Intel or AMD Ryzen platforms, then click the “Test” menu at the top of the Prime95 window and select “stop” or “exit”. Do not simply click the "X" in the top right corner as that will NOT stop the stress test, it will only minimize it to the tray.

You MUST click Stop or Exit from the drop down TEST menu at the top left of the window to stop the stress test.

Alternatively, you can run the OCCT Small data set, also with AVX disabled. Same process.


If you have an AMD system, then measuring thermals is going to be a little different.

AMD does not design their platforms in a way that does not make, by any definition, measuring core temps accurate or reliable. On the low end of the scale their thermal sensor readings have long been laughable, sometimes showing temps that are well below what the ambient temperature is, which of course is not possible without some kind of Peltier cooler or active refrigeration. At the other end of the thermal range it’s not much better.

This is because AMD does not actually implement their sensor designs to be determined in the same way that Intel does. AMD uses a method known as distance to Tjmax. Tjmax being, in this case, the temperature at which AMD has determined bad stuff will start happening such as thermal throttling, shut downs and damage.

For this reason when you are testing thermal compliance, or just monitoring for general purposes, you need to be aware of this difference and purposely either use applications designed for use with AMD processors or make some settings changes in other utilities that will allow you to see distance to Tjmax rather than estimated core temps.

There are a couple of ways you can do this. First off, HWinfo generally has the appropriate fields which are labeled as Distance to Tjmax. I feel like the better choice though is either CoreTemp or AMD overdrive for monitoring Distance to Tjmax on AMD platforms. In CoreTemp you will need to go into the Options tab, click on Settings and on the Advanced tab check the box next to the setting for “Show distance to Tjmax in temperature fields” in order to change from the default and likely inaccurate core temperature display.

AMD overdrive shows Distance to Tjmax by default, and I don’t think there is any other way to monitor CPU thermals in that utility anyhow. Either of these is probably a good choice, but it’s also likely worth checking either CoreTemp or AMD overdrive against what you see for Distance to Tjmax in HWinfo and if the readings are pretty close to the same, just use HWinfo as there is a lot of other information available in the sensors display that is not available with these other two.

Regarding the actual Distance to Tjmax sensor readings, what you do NOT want to see is anything closer than 10°C Distance to Tjmax, ESPECIALLY if you are only in the first phase of your overclock configuration and have only made minor changes to the CPU multiplier and voltage at this point. If it drops below ten degrees to Tjmax you are getting very close to your thermal ceiling and need to revisit either your cooling solution or voltage settings.

If you can run the Prime95 version 26.6 or 29.8 (With AVX/AVX2 disabled) Small FFT torture test for 15 minutes without exceeding 80°C for Intel/AMD Ryzen or dropping below 10°C thermal margin (AKA Distance to Tjmax) for AMD, then you are to some degree or other within specification for thermal tolerance.

If you are very close to the edge however, this may be a warning sign that you don’t have much overclocking headroom since we’ve only barely set our multiplier to what is basically the all core equivalent of the default single core Turbo frequency (Speed). IF that is the case, you will want to either be very careful going forward or stop and think about upgrading your CPU cooler and perhaps looking at whether your case and case fan situation is really sufficient for what you are trying to do.


Testing stability

So, if you passed the thermal compliance phase the next step will be to test stability. I cannot over stress the importance of not cutting corners when it comes to stress testing. Do not listen to naysayers who try to tell you that if you simply run this or that for 15 minutes, or an hour, or can pass a specific benchmark without errors, that your system is stable. Do not listen to people who say that if it is only a gaming system then stability isn’t important so long as it doesn’t crash. This is unreliable.

It IS important, no matter WHAT you do on the system. Unstable CPU or memory configurations can thoroughly degrade an operating system, game files or other parts of your file system to the point of eventually making them unusable. Instability is also probably not the best thing for the hardware itself.
Do the tests. Do them for the length of time they should be done for and do not cut corners even though it is tempting to do. You will only be hurting yourself in the long run.

Open Realbench and run a 1 hour stress test to begin with. Choose the Stress test option by clicking on the Stress test button. Choose the one hour option. Set the memory option to approximately half of your total installed memory. We are not worried about testing memory right now. If you have more than 16GB of memory, choose the up to 16GB option. If you have 16GB of memory, choose the up to 8GB option. If you have 8GB or less, choose the up to 4GB option.

If you pass the 1 hour stress test and plan to try increasing your overclock a bit higher, then you can start again just as you did in the beginning but bump the CPU core frequency up by another 100-200mhz. If it will post and boot into windows, repeat the thermal test and the stress test.
If it will not POST and boot into windows, or if you get errors or bluescreens at any point, then you will need to bump up your CPU core voltage a bit and try again. We went over that in the beginning so that should be self explanatory at this point.


If you were not able to pass the one hour stress test, then also, you will want to go back into the bios and bump the voltage up a small amount. By small amount, I mean whatever minimal increment the BIOS will allow you to adjust it upwards in. If the voltage was at 1.32v and did not pass, or would not POST, or there were errors or bluescreens or the screen went black and (**)restarted then try bumping the CPU core voltage up to 1.325. If it was at 1.3v try 1.31. Etc.

(**Assuming it did not do so because of a low quality power supply. Very important to have a high quality power supply if you are going to be overclocking. Watts are not the only consideration. A unit with good, clean power that has low ripple and electrical noise is very important in order for the motherboard and voltage regulators to remain stable and not overheat as well.)

Every time you make a change in the bios to increase the CPU core voltage, YOU MUST RUN the thermal tests again to verify you are still within tolerance.

If however you passed the one hour stress test with no errors, no problems of any kind, and do not wish to raise the level of your overclock, or at any time if you get to the point where you are happy with the speed you have achieved up to that point, then you can go ahead and run the Realbench stress test again except this time run it for a full 8 hours.

If it passes that, then close Realbench and open Prime95 again. Choose the Blend test and run that for 8 hours. If it passes that, your system is probably about as stable as can be expected under almost any circumstances and you can call it a day if you are able to pass both of these tests and are still within thermal compliance. It’s worth noting that you may want to periodically check your maximum thermal readings on your monitoring software which you should leave running alongside any stress tests, just to make sure that you don’t exceed thermal limits while testing.

If you remained below the thermal ceiling when you ran the Small FFT Prime95 torture test though, you should not have any issues with thermals on either of these other tests anyway.
If you wish to take the stability testing one step further IN ADDITION to having passed both the Realbench 8 hr test and the Prime95 Blend mode 8 hr test, you can run Prime95 Small FFT for 24 hours and if you pass that there is little else you can do to assure that your system is stable in regard to your CPU overclock settings.

At this point you can move on to using your system normally again, or, if you wish to push things a little further to see how much more you can squeeze out of it, then you can simply start the whole process over again moving up incrementally from where you left off but it is terribly important that you always perform the thermal and stability tests after any changes so you don't end up creating tremendous problems for yourself later on or inadvertently damaging your hardware with an overclock that is beyond what your cooling system, motherboard and CPU are capable of sustaining.

If you have successfully achieved the overclock you were hoping for, then congratulations and at this point you can reconfigure your memory XMP settings or continue on to either tightening your memory timings or overclocking your memory, if you plan to do so.​
 
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Kvnnon

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Feb 23, 2019
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No, that would be a completely wrong configuration. Top and rear fans should ALWAYS be exhaust, in 99.9% of configurations, and in 100% of tower case configurations, while front, bottom and side fans should always be configured as intake fans. Power supply, when bottom mounted, should, in about 99% of configurations, be facing it's intake grill down, not into the case, and be completely separate as far as airflow is concerned, from the rest of the internal case, and venting out the back.

So, for almost all cases, and pretty much ALL tower ATX cases, front intake, rear and top exhaust. On those few cases with side panel fan locations, those should also be intake. IF you can squeeze a fan into the bottom of the case, if there is a fan location there, that too should be intake, but it's rare that anybody can use those.


Testing thermal compliance

Once you get to the Windows desktop, the first thing you will want to do is open HWinfo (Sensors only option), Core Temp or Ryzen Master and take a look at what your core and package temperatures are doing. At idle your core temps should be somewhere below 40°C in the majority of cases. Preferably somewhere in the mid to low 30’s. On some newer very high core count models, or if you are using the stock cooler (In which case you shouldn't be overclocking anyhow), then it might not be below the 40°C threshold.

If you are not overclocking and are ONLY testing the thermal compliance of the stock configuration, then don't be TOO concerned by a high idle temperature UNLESS you also have a high load temperature that is outside of spec. This WILL be affected by whatever the ambient temperature is in the room where you are, so if your are in a very warm region and have no air conditioning going you may have an idle temp that is a bit closer to 40. For cooler ambient rooms or regions it will likely show low 30’s-ish. Be aware that unless you have excessively high idle temps, say, above 40°C, then what your actual idle temps are is practically irrelevant. Cooler idle temps are not indicative of much of anything specific.

Very HIGH idle temps however DO indicate that there is likely a problem with an incorrectly installed CPU cooler heatsink, too high of CPU core voltage or some other cooling or voltage related issue. If you are using one of those other utilities I warned about in the beginning of this tutorial, it may also be that the utility is reporting falsely. In that case, go get HWinfo or CoreTemp and check again.

If idle temps seem fine, then leave your monitoring application open and run Prime95 (Either version 26.6 or the latest version with AVX/AVX2 disabled).

Choose the Small FFT option (NOT "Smallest FFT") and allow it to run for fifteen minutes. If you are using the latest version of Prime95 (Version 29.8 or newer) then you NEED to be sure to disable the AVX and AVX2 options in the main options window. When you disable AVX2 the option to disable AVX will become available. If at any point your core or package temperatures exceed 80°C for Intel or AMD Ryzen platforms, then click the “Test” menu at the top of the Prime95 window and select “stop” or “exit”. Do not simply click the "X" in the top right corner as that will NOT stop the stress test, it will only minimize it to the tray.

You MUST click Stop or Exit from the drop down TEST menu at the top left of the window to stop the stress test.

Alternatively, you can run the OCCT Small data set, also with AVX disabled. Same process.


If you have an AMD system, then measuring thermals is going to be a little different.

AMD does not design their platforms in a way that does not make, by any definition, measuring core temps accurate or reliable. On the low end of the scale their thermal sensor readings have long been laughable, sometimes showing temps that are well below what the ambient temperature is, which of course is not possible without some kind of Peltier cooler or active refrigeration. At the other end of the thermal range it’s not much better.

This is because AMD does not actually implement their sensor designs to be determined in the same way that Intel does. AMD uses a method known as distance to Tjmax. Tjmax being, in this case, the temperature at which AMD has determined bad stuff will start happening such as thermal throttling, shut downs and damage.

For this reason when you are testing thermal compliance, or just monitoring for general purposes, you need to be aware of this difference and purposely either use applications designed for use with AMD processors or make some settings changes in other utilities that will allow you to see distance to Tjmax rather than estimated core temps.

There are a couple of ways you can do this. First off, HWinfo generally has the appropriate fields which are labeled as Distance to Tjmax. I feel like the better choice though is either CoreTemp or AMD overdrive for monitoring Distance to Tjmax on AMD platforms. In CoreTemp you will need to go into the Options tab, click on Settings and on the Advanced tab check the box next to the setting for “Show distance to Tjmax in temperature fields” in order to change from the default and likely inaccurate core temperature display.

AMD overdrive shows Distance to Tjmax by default, and I don’t think there is any other way to monitor CPU thermals in that utility anyhow. Either of these is probably a good choice, but it’s also likely worth checking either CoreTemp or AMD overdrive against what you see for Distance to Tjmax in HWinfo and if the readings are pretty close to the same, just use HWinfo as there is a lot of other information available in the sensors display that is not available with these other two.

Regarding the actual Distance to Tjmax sensor readings, what you do NOT want to see is anything closer than 10°C Distance to Tjmax, ESPECIALLY if you are only in the first phase of your overclock configuration and have only made minor changes to the CPU multiplier and voltage at this point. If it drops below ten degrees to Tjmax you are getting very close to your thermal ceiling and need to revisit either your cooling solution or voltage settings.

If you can run the Prime95 version 26.6 or 29.8 (With AVX/AVX2 disabled) Small FFT torture test for 15 minutes without exceeding 80°C for Intel/AMD Ryzen or dropping below 10°C thermal margin (AKA Distance to Tjmax) for AMD, then you are to some degree or other within specification for thermal tolerance.

If you are very close to the edge however, this may be a warning sign that you don’t have much overclocking headroom since we’ve only barely set our multiplier to what is basically the all core equivalent of the default single core Turbo frequency (Speed). IF that is the case, you will want to either be very careful going forward or stop and think about upgrading your CPU cooler and perhaps looking at whether your case and case fan situation is really sufficient for what you are trying to do.


Testing stability

So, if you passed the thermal compliance phase the next step will be to test stability. I cannot over stress the importance of not cutting corners when it comes to stress testing. Do not listen to naysayers who try to tell you that if you simply run this or that for 15 minutes, or an hour, or can pass a specific benchmark without errors, that your system is stable. Do not listen to people who say that if it is only a gaming system then stability isn’t important so long as it doesn’t crash. This is unreliable.

It IS important, no matter WHAT you do on the system. Unstable CPU or memory configurations can thoroughly degrade an operating system, game files or other parts of your file system to the point of eventually making them unusable. Instability is also probably not the best thing for the hardware itself.
Do the tests. Do them for the length of time they should be done for and do not cut corners even though it is tempting to do. You will only be hurting yourself in the long run.

Open Realbench and run a 1 hour stress test to begin with. Choose the Stress test option by clicking on the Stress test button. Choose the one hour option. Set the memory option to approximately half of your total installed memory. We are not worried about testing memory right now. If you have more than 16GB of memory, choose the up to 16GB option. If you have 16GB of memory, choose the up to 8GB option. If you have 8GB or less, choose the up to 4GB option.

If you pass the 1 hour stress test and plan to try increasing your overclock a bit higher, then you can start again just as you did in the beginning but bump the CPU core frequency up by another 100-200mhz. If it will post and boot into windows, repeat the thermal test and the stress test.
If it will not POST and boot into windows, or if you get errors or bluescreens at any point, then you will need to bump up your CPU core voltage a bit and try again. We went over that in the beginning so that should be self explanatory at this point.


If you were not able to pass the one hour stress test, then also, you will want to go back into the bios and bump the voltage up a small amount. By small amount, I mean whatever minimal increment the BIOS will allow you to adjust it upwards in. If the voltage was at 1.32v and did not pass, or would not POST, or there were errors or bluescreens or the screen went black and (**)restarted then try bumping the CPU core voltage up to 1.325. If it was at 1.3v try 1.31. Etc.

(**Assuming it did not do so because of a low quality power supply. Very important to have a high quality power supply if you are going to be overclocking. Watts are not the only consideration. A unit with good, clean power that has low ripple and electrical noise is very important in order for the motherboard and voltage regulators to remain stable and not overheat as well.)

Every time you make a change in the bios to increase the CPU core voltage, YOU MUST RUN the thermal tests again to verify you are still within tolerance.

If however you passed the one hour stress test with no errors, no problems of any kind, and do not wish to raise the level of your overclock, or at any time if you get to the point where you are happy with the speed you have achieved up to that point, then you can go ahead and run the Realbench stress test again except this time run it for a full 8 hours.

If it passes that, then close Realbench and open Prime95 again. Choose the Blend test and run that for 8 hours. If it passes that, your system is probably about as stable as can be expected under almost any circumstances and you can call it a day if you are able to pass both of these tests and are still within thermal compliance. It’s worth noting that you may want to periodically check your maximum thermal readings on your monitoring software which you should leave running alongside any stress tests, just to make sure that you don’t exceed thermal limits while testing.

If you remained below the thermal ceiling when you ran the Small FFT Prime95 torture test though, you should not have any issues with thermals on either of these other tests anyway.
If you wish to take the stability testing one step further IN ADDITION to having passed both the Realbench 8 hr test and the Prime95 Blend mode 8 hr test, you can run Prime95 Small FFT for 24 hours and if you pass that there is little else you can do to assure that your system is stable in regard to your CPU overclock settings.

At this point you can move on to using your system normally again, or, if you wish to push things a little further to see how much more you can squeeze out of it, then you can simply start the whole process over again moving up incrementally from where you left off but it is terribly important that you always perform the thermal and stability tests after any changes so you don't end up creating tremendous problems for yourself later on or inadvertently damaging your hardware with an overclock that is beyond what your cooling system, motherboard and CPU are capable of sustaining.

If you have successfully achieved the overclock you were hoping for, then congratulations and at this point you can reconfigure your memory XMP settings or continue on to either tightening your memory timings or overclocking your memory, if you plan to do so.​
Thanks for this advice mate. While running CoreTemp with a game running in the background, the Mins were 70 and the Max was 80. This seems extremely high for running a game. Do you suggest I reapply thermal paste and if I do not see thermals drop contact CoolerMaster and see if I can get a replacement?