Help! Why Won't My CPU Cool Down?

[evan2k7]

I'm running a custom build that I made at the beginning of the year. My PC ran fine for about 7 months and then suddenly my games slowed to a stutter and my computer was subject to random shutdowns/reboots. After doing some troubleshooting I've realized that the issue is my CPU is running way too hot.

I have an i7-7600k (still running at stock speeds), and my temp readings are constantly coming out at about 99 degrees Celsius which is causing my CPU speeds to seriously throttle and makes something as simple as web browsing noticeably slower. The CPU is being cooled with a Corsair H00iv2 water cooler which doesn't seem to have any issues going on with it. I've also tried cleaning and reapplying thermal paste (Cooler Master) twice, which gets me my original performance for all of 15 minutes before temperatures rise back up again.

I've checked these temperatures from multiple sources on my PC (MSI Command Center, Corsair Link, the digital display on my MoBo) and they're giving the same results. I don't see any other readings that are coming out abnormally. I can still feel the proper airflow coming from my fans/radiator, and I haven't made any significant changes to my build since this problem started occuring (save for switching for a larger power supply, but like I said, that was after the problem began). Is there anything I may be missing that is causing my CPU temps to skyrocket like that?

 

[HamBown81]

If you have changed nothing and have tried new thermal paste I would suspect the AIO.

Are both the inlet and outlet tubes warm?
Is your radiator clean?
Can you hear gurgling or bubbling sounds?
Does changing the pump speed affect the temperature?

 

[JackNaylorPE]

Given what you have described I see two possible options:

a) The system has become clogged at some point due to galvanic corrosion. With an aluminum radiator and copper block CLCs create a galvanic corrosion cell. Corrosion inhibitors have a usable life of 18 - 24 months at which point they offer little protection and, in a CLC, they can not be replaced. In a galvanic cell, the lesser noble metal sacrifices electrons (like a sacrificial zinc on a boat) that flow to the block. This is the result

https://martinsliquidlab.wordpress.com/2012/01/24/corrosion-explored/

At just 7 months old, I don't see this being the case in your system.

b) The pump has failed and water is not circulating.

c) Somehow you managed to get an air pocket in there which is resisting flow

For this reason we recommend using only OLC type AIOs which use copper radiators:

-Copper thermally more efficient
-No mixed metals
-Corrosion inhibitors can be added
-Strong 1.0 + gpm pumps (100i is 0.11 gpm)
-Visible fluid in reservoir allows you to see pump flow
-System is expandable ... can add additional blocks and rads
-As copper rad more thermally efficient, no need for extreme speed fans
- You can bleed out air pockets

http://www.swiftech.com/h220x2.aspx

 

[evan2k7]

If you have changed nothing and have tried new thermal paste I would suspect the AIO.

Are both the inlet and outlet tubes warm?
Is your radiator clean?
Can you hear gurgling or bubbling sounds?
Does changing the pump speed affect the temperature?

I'm pretty sure that my radiator is clean. I gave it a good cleaning when these issues first started popping up.
As for the inlet/outlet tubes, one of them is warm where it meets the base of the heatsink (not sure which one it is), but the other doesn't seem to have any warmth to it.
I feel like I can hear some light bubbling sounds going through the tubes. All of the PC/cooler fans are running really loud though, so its kind of drowned out (hoping I'm not imagining it).

**I did end up going into Corsair Link to change the pump speed. On the home menu it does have the H100i v2 pump displaying 0 rpm. Switching from quiet to performance mode didn't seem to change anything. I've never tinkered with any of this before as my PC met all of my needs upon initial setup, but should I take this as a sign of some sort of pump failure?

 

[HamBown81]

I'm pretty sure that my radiator is clean. I gave it a good cleaning when these issues first started popping up.
As for the inlet/outlet tubes, one of them is warm where it meets the base of the heatsink (not sure which one it is), but the other doesn't seem to have any warmth to it.
I feel like I can hear some light bubbling sounds going through the tubes. All of the PC/cooler fans are running really loud though, so its kind of drowned out (hoping I'm not imagining it).

**I did end up going into Corsair Link to change the pump speed. On the home menu it does have the H100i v2 pump displaying 0 rpm. Switching from quiet to performance mode didn't seem to change anything. I've never tinkered with any of this before as my PC met all of my needs upon initial setup, but should I take this as a sign of some sort of pump failure?

I would say yes. The gurgling is an indication that there is air in the system and only one side of the tubing being warm is an indication that the pump isn't running properly (or at all).

The easiest way to confirm would be to throw a different CPU cooler on there. Even the stock cooler should perform better than what you are reporting.