Cpu temp sensor bad? I’ve tried everything and can’t figure it out.

[Letro28]

I’ve had my computer for about a year, which I built myself along with help from more experienced friends, and just recently I’ve noticed some severe lagging in games that shouldn’t be experiencing that, such as Roblox and Hunt: Showdown, which have never experienced lag like this before. A friend then recommended that I install CoreTemp to see if it’s my cpu, to which I did and read that my cores were running into the 80s and 90s (Celsius) with a minor load to the cpu and minimal usage. Taking this into consideration I freaked out and bought both a brand new Kraken dual X53 AIO cooler from BestBuy (upgrade from my intel stock fan) and a used, but in good condition, intel i7-9400k. To which I started experiencing the same problems with my cpu idling around 70-80 Celsius while even in bios. I also ran a SpyBot scan to which it found malware but it didn’t seem to help at all after removing, with my case having ample airflow and my heatsink being seated properly, along with a new coat of Corsair thermal paste. Is my cpu temp sensor bad? I don’t understand what else could be the problem if both my CPU’s were running that hot with different coolers and ample thermal paste. Any input is appreciated!
 

my specs:

MSI Z390 Gaming plus mobo

i5-9400F (upgraded to an i7-9400k)

gigabyte GeForce GTX 1060 3GB GDDR5 

DDR4 Crucial 16 GB ram

Kraken X53 Dual AIO cooler 

 

[Bismut]

Hi, the CPU temp sensor should be built into the CPU itself, I have never heard of one dying and would say that it's highly unlikely that they're dead in both of the CPUs. I would check what the fan curve is set to in the BIOS and go for a more agressive one than you have at the moment. If that doesn't help, try to re-apply the thermal paste on your cooler (I have used MX-2, but anything that came with the Kraken should be fine too, as long as it wasn't pre-applied) and blow out any dust filters on your case (or just teke them off temporarily), as well as check that the case fans are working.

[Letro28]

1 hour ago, Bismut said:

Hi, the CPU temp sensor should be built into the CPU itself, I have never heard of one dying and would say that it's highly unlikely that they're dead in both of the CPUs. I would check what the fan curve is set to in the BIOS and go for a more agressive one than you have at the moment. If that doesn't help, try to re-apply the thermal paste on your cooler (I have used MX-2, but anything that came with the Kraken should be fine too, as long as it wasn't pre-applied) and blow out any dust filters on your case (or just teke them off temporarily), as well as check that the case fans are working.

The case fans are working and there should be minimal dust as it has stayed very clean. Im just stumped as to why both cpus are acting funny out of nowhere. I applied my own thermal paste and made sure it had good spread too. I’ll try again here soon, thank you!

[An0maly_76]

Fans are only part of the formula. You must have airflow. Listing your full specs including case will further help us to help you.

[Letro28]

1 hour ago, An0maly_76 said:

Fans are only part of the formula. You must have airflow. Listing your full specs including case will further help us to help you.

My case is a Sama-3D Black Steel. It had prebuilt fans that worked seemingly  well as I had good ventilation which caused no overheating issues as far as I know until this point. Even while only running the stock intel cooler until just recently. My case configuration has one intake one outtake while the top two slots were replaced with the fans that connect to the radiator of my cooler as that was the only way it would fit. I also noticed while my cpu says it’s hitting high Celsius temps it seemingly radiated no heat and my radiator stayed cold the whole time. 

[PwnyTheTiger]

There really is no reason the CPU should be getting that hot under no load, which would be indicative of either; mounting pressure, airflow problems, or not enough thermal paste. If I read your original post correctly, you changed the CPU, which also is running too hot which would rule out any sort of issue with a temp sensor, especially considering it's build into the die. Have you checked the thermal paste application after mounting? Just simply pull it off and see if it's actually evenly covering the entire IHS and cooler. Considering this just suddenly happened out of no where, it would lead me to believe it's one of the above reasons, or it could be an unintentional OC set in the BIOS, or one(or multiple) of your fans are dying or slowed down.

[Letro28]

12 minutes ago, PwnyTheTiger said:

There really is no reason the CPU should be getting that hot under no load, which would be indicative of either; mounting pressure, airflow problems, or not enough thermal paste. If I read your original post correctly, you changed the CPU, which also is running too hot which would rule out any sort of issue with a temp sensor, especially considering it's build into the die. Have you checked the thermal paste application after mounting? Just simply pull it off and see if it's actually evenly covering the entire IHS and cooler. Considering this just suddenly happened out of no where, it would lead me to believe it's one of the above reasons, or it could be an unintentional OC set in the BIOS, or one(or multiple) of your fans are dying or slowed down.

I ended up applying thermal paste probably 5 separate times and cleaned it off with 70% isopropyl as that’s what I had at my disposal. Every time I pulled it off to reapply or clean it, it seemingly appropriately covered the heatsink. I’ll definitely check bios to see if any settings are wonky, it’s just sort of difficult due to my cpu reaching high temps while in bios for more than 10 minutes or so, so it makes me feel slightly rushed when dealing with it as to not damage my computer further. On the other hand all my fans seemed to be running at good speeds and worked well. I’ll try and clean off my heatsink here soon and reapply smaller amounts of thermal paste to see if that helps anything. Thank you very much for your input!

[PwnyTheTiger]

1 minute ago, Letro28 said:

I ended up applying thermal paste probably 5 separate times and cleaned it off with 70% isopropyl as that’s what I had at my disposal. Every time I pulled it off to reapply or clean it, it seemingly appropriately covered the heatsink. I’ll definitely check bios to see if any settings are wonky, it’s just sort of difficult due to my cpu reaching high temps while in bios for more than 10 minutes or so, so it makes me feel slightly rushed when dealing with it as to not damage my computer further. On the other hand all my fans seemed to be running at good speeds and worked well. I’ll try and clean off my heatsink here soon and reapply smaller amounts of thermal paste to see if that helps anything. Thank you very much for your input!

Just simply reset your BIOS settings, should be some option to revert to defaults.

[An0maly_76]

As I said, fans are only part of the formula. It's placement, orientation, case airflow, ventilation and even fan motor speed. Here's one crucial part of the puzzle right here, this is how your fans should be oriented. The basics in most situations are that you need cool air coming in the front, hot air going out the top and back. If they're fighting each other, your airflow becomes a gridlock that doesn't do anything. Blue = cool air in, red = hot air out.

 

Edited July 4, 2022 by An0maly_76
Revised, more info

[Letro28]

36 minutes ago, An0maly_76 said:

As I said, fans are only part of the formula. It's placement, orientation, case airflow, ventilation and even fan motor speed. Here's one crucial part of the puzzle right here, this is how your fans should be oriented. The basics in most situations are that you need cool air coming in the front, hot air going out the top and back. If they're fighting each other, your airflow becomes a gridlock that doesn't do anything. Blue = cool air in, red = hot air out.

 

I think I have them set up correctly as I followed guides and did my best to set it up similar to others, with the airflow being set to have a constant flow of motion through the case and out the back and top but I could always double check. Here’s a picture of my arrangement just in case too.

[PwnyTheTiger]

That really isn't ideal to be honest, especially considering you have nothing at the top to push that hot air up and out of the system, plus the case you have doesn't really have the best airflow in the front of it, if it is the model with the little strip going along the middle of the front panel. Having a rad in front with the fans in front pushing air through and inside the system isn't much of an issue but also isn't ideal as it's literally dumping whatever heat the CPU is pushing out into the system. If you can mount the AIO on top with fans pushing through and up in the same way, along with adding 2-3 fans on the front for airflow you might see better results from the temps. Otherwise even adding 1-2 fans to the top would likely help, if airflow is indeed the issue.

 

Before all that, I'm curious if you can see the temp of the AIO block? On my Corsair Capellix, I can see the temp of the actual pump unit which usually runs 35-40 while the CPU maxes out at 70ish. I'm curious if those temps are raised up as well and how badly, if they are.

[Letro28]

6 minutes ago, PwnyTheTiger said:

That really isn't ideal to be honest, especially considering you have nothing at the top to push that hot air up and out of the system, plus the case you have doesn't really have the best airflow in the front of it, if it is the model with the little strip going along the middle of the front panel. Having a rad in front with the fans in front pushing air through and inside the system isn't much of an issue but also isn't ideal as it's literally dumping whatever heat the CPU is pushing out into the system. If you can mount the AIO on top with fans pushing through and up in the same way, along with adding 2-3 fans on the front for airflow you might see better results from the temps. Otherwise even adding 1-2 fans to the top would likely help, if airflow is indeed the issue.

 

Before all that, I'm curious if you can see the temp of the AIO block? On my Corsair Capellix, I can see the temp of the actual pump unit which usually runs 35-40 while the CPU maxes out at 70ish. I'm curious if those temps are raised up as well and how badly, if they are.

The problem I’m running into is I also bought a 1TB m.2 from the same guy I bought the i7 from and in bios it’s not letting me access my previous HDD or SSD that are connected via SATA, which my windows was running from, so now I’m stuck without my personal windows to download the application to display that on my block. The other thing is I tried to mount my radiator to the top of my case but the MSI cover near the back USB ports sticks out too far and blocks me from being able to do so. I have some extra fans which I’ll try and mount up here soon. Thank you! 

[PwnyTheTiger]

Most motherboards disable certain SATA slots when you install a m.2, look into if your motherboard does that. Otherwise just take it out for the time being.

[An0maly_76]

1 hour ago, PwnyTheTiger said:

That really isn't ideal to be honest, especially considering you have nothing at the top to push that hot air up and out of the system, plus the case you have doesn't really have the best airflow in the front of it, if it is the model with the little strip going along the middle of the front panel. Having a rad in front with the fans in front pushing air through and inside the system isn't much of an issue but also isn't ideal as it's literally dumping whatever heat the CPU is pushing out into the system. If you can mount the AIO on top with fans pushing through and up in the same way, along with adding 2-3 fans on the front for airflow you might see better results from the temps. Otherwise even adding 1-2 fans to the top would likely help, if airflow is indeed the issue.

 

1 hour ago, PwnyTheTiger said:

Most motherboards disable certain SATA slots when you install a m.2, look into if your motherboard does that. Otherwise just take it out for the time being.

THIS and this. Also, I'm not seeing any listings for an i7-9400K. I'm not saying that means it doesn't exist, but are you sure of the model?