Inconsistent CPU Temps on an i7 4790K in new water cooled loop

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I built my first water cooling loop today. Everything runs fine with no leaks or anything however, my CPU is getting random temp spikes. when CPU load is at 0-10%, the temps are sitting cool around the low 30C's. However, once the load goes any higher, the temps jump to anywhere between the mid 40's and the low 60's Inconsistently. Once the load goes away, the temps immediately drop back down. Its not even a gradual drop back to the idle temps, its just instant based on the readings from Core Temp, SpeedFan, and HWMonitor. I've tried reapplying thermal paste already and as far as I can tell there isn't any more air left in the system. I've tried to google the issue but haven't found anything that matches this particular problem. Any help is greatly appreciated! :??:

Build:
i7 4790k (OC at 4.4Ghz) CPU
Corsair 750D Case
Radeon R9 290 GPU
MSI Z97S Krait Edition Mobo
Crucial 256Gb SSD
Seagate 3Tb HDD
32Gb DDR3 Corsair Dominator Platinum

WC Parts:
EK Supremacy EVO CPU WB
EK FC-R9 290 GPU WB
250mL res
360mm Triple Rad
Swiftech MCP655
 

Crapcicle

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Temps work like that. I get the same kinds of readings and I'm using an air cooled system! They drop down immediately once the load is removed. Nothing really wrong with your cooling bud. Btw are these higher temps recorded during a benchmark such as prime95 or realbench?
 

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No these are just common tasks like opening a few internet browsers or launching a program. I was just playing Far Cry 4 and my CPU temps were in the low 90's so i turned it off but my GPU was sitting at 45 with the settings on high. When i first booted my PC earlier today, I ran FurMark and after initially getting started, the CPU temps stabilized at around 55 for the duration of the test which i ran for 20 minutes
 

Crapcicle

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That is very strange. Download ASUS realbench and tell me your CPU temps then. But playing Farcry 4 at low 90's is indeed very dangerous. Do you have any pictures of your cooling loop?
 

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Here is the best I could get of the system
System

This first one is the realbench temps. the very first spike was from starting CPU Burn from the FurMark test and then shutting it off. The gradual rise from the 30-60's was the image editing portion of the realbench. The jump to the high 90's was the video encoding. The drop and then rise to mid 90's was the OpenCL test and the last set of high 90's again is the heavy multitasking portion of the test.
RealBench Temps

This second one is the temps while I was playing Far Cry 4 last night
Far Cry Temps
 

Crapcicle

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From your loop it seems like the GPU and CPU are sharing one cooling loop? That is why your temps are so high. They are both applying heat to the liquid. Which means that when the GPU gets hotter it then travels to the CPU and vice versa. Eventually the liquid gets really hot from having a 60+ degree Celsius card and a 70+ degree Celsius CPU. If you put them on separate loops it should solve your problem. Or you can also just go air cooling, that would probably fix it too.
 

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The GPU flows to the radiator first to expel heat and then to the CPU. The cpu is the last item in the loop to get cooled before water gets returned to the reservoir. I would understand if my gpu flowed directly to my cpu but it doesn't and even if it did, the gpu temps haven't gone over 45 so its not much additional heat
 

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Did the temps change? Also ambient temperatures also affect watercooling systems as much as air cooled systems because the radiator still uses air as a medium for cooling. What do your ambient temps look like?
 

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I use regular distilled water with no additives and have an EK-CoolStream PE 360(Triple) radiator. Perhaps there is some air in the rad(I would hear that though, wouldn't I?) that is limiting flow to the CPU??
 

Crapcicle

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Maybe. But i don't think that would cause 90+ temps. Your motherboard isn't overheating either right? It's strange that it's just your CPU. Did you come from an air cooling solution or did you build the cooling loop from the start? If you have an extra heatsink maybe you can try and see the temps on air cooling. I am really confused as to why your CPU is at 90+ temps even at 0.9v. I'm running an air cooled i5-4690k @ 4.4 and 1.25v and my temps never go above 50-60 degrees playing a CPU intensive game like ARMA 3 and never go past 80 during realbench and prime95.
 

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I moved from air cooling. I had a Hyper 212 EVO on it before hand. I'm not really sure what my temps were with air cooling though because I was more worried about my GPU (which idled in the low 60's). [strike]The motherboard temps rise and fall with the CPU temps. I just started monitoring them. Ran a couple benchmarks to watch it[/strike]

Edit:
The motherboard stays steady at 33-35. I misread the color layout. One of the CPU cores was green and so was the motherboard color on the speedfan graph chart. I flipped them.
 

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Ok so I may not have to actually. I was trying to waste time while I cooked dinner so I fired up Far Cry 4 again and this time the temps stabilized at 60 which is considerably better. I think maybe it just needs to run for awhile?
 

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Maybe your cooling loop was just breaking itself in? Is there such a thing? You should probably write a thesis on it. You would probably win an award or something for discovering a singularity in water cooling systems.