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New to water cooling. CPU runs too hot. Over 80°

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New Member
Aug 10, 2016

i just build my first custom water loop and am seriously disappointed by the result. And im looking forward to getting some feedback from more experienced water cooling users.
So first of all, this is my water cooling setup that i got used from ebay:
-Hardware Labs Black Ice Lite 360 Radiator
-Aquacomputer XT Advanced
-Bitspower 150mm Water Tank
-EK Water Blocks EK-Supremacy - Acetal+Nickel CPU Kühler
-3 x Noiseblocker Black Silent Pro Fan PL2 attached to motherboard. In Push configuration

I am currently only having the CPU in the loop, no GPU so far.

My CPU: i5 4670K@4,3GHz and 1,23 V

This is the overclocking setting which I set up when still using air cooler. My core temps went up to 98° under LinX/Prime95. So way too hot for benchmarks but completely stable in games.
Now I was hoping too seriously reduce these load temps when switching to water cooling, especially when having a 360mm radiator just for the CPU.

With my first build, the core temperatures went up to 92° with distilled water in the loop. So I drained it the next morning, checked for residues (water was totally clean). I then removed the "anti cyclone" adapter from the reservoir thinking that it inhibits water flow. I also reapplied the thermal paste and reseated the CPU block. Now the temperatures for the cores still reach 82° and the CPU temp readout from AIDA64 says 68°.

Now my question is, if this is all I can expect from this setup or if there is something wrong. Temps of 82° for the core seems way too high for me with this overclock.
Any tips on how to lower the temps? Is it worth investing into a flow meter to see if this is an issue?
I can take some pictures of my setup if that helps you out. Though be warned, my hard tubing skills for my first build ever really su**ed :-D
There is probably some air stuck in your loop somewhere attach a picture and maybe we can spot something you missed.
Lastly make sure the water flow through the cpu block is the right direction.
Thanks for the quick reply. I am not sure how to tell if there is still air left in the system. I did move it quite a lot initially with one opening in the reservoir to get most of the air out at the beginning.
I have taken some pictures:
2016-08-10 16.47.58-min.jpg 2016-08-10 16.48.20-min.jpg 2016-08-10 16.48.35-min.jpg

I also took some pictures when I took of the cpu block and reseated it. These pictures show how much thermal paste I applied in the first place and how it distributed under pressure. When I applied it again, i used a bit less paste.

2016-08-10 09.47.24-min.jpg 2016-08-10 09.47.29-min.jpg
I'm thinking there's air inside that eheim pump. Also in pic #2 there's a large air bubble trapped in that curve feeding the block. You're going to have to tilt the case in all directions while the pump is running to start bleeding the system.
Okay, I think I did get some air out of the system. From 68° to 65°.

Just two quick questions:
1. Will the pump be alright if I tilt the case up to 90 degree while bleeding.
2. Do I have to keep one inputs of the reservoir open for air to get out while bleeding or can i close it to give me some more space to tilt the case further?
1. As soon as the liquid in the res is above the pump, no pb.
2. Nope, it's a closed loop, so the air and coolant will move, but nothing is added or removed, so no need to open the res.
Look at the reservoir and visualize the movement of water flow to it. Is it turbulent or a slow flow to it?

Also, is the radiator warm to the touch when benchmarking? Usually, a newer version of Prime95 makes the CPU's very toasty as you're better off with someone of the older versions.
The fitting that I circled in your pic appears to have a kink right at the block. Optical delusion or what? Might want to make that a bit smoother (more radius).

Ok, thanks for your help. I tried to get all the air out of the system and it seems to help.
Regarding the smoothness of the bends: I guess you are right, its not the best bending but as far as I can see there are also no real kinks in there as well.
And I also cant really see turbulences in the reservoir, maybe some right when turning the system on but not while it is running.

I used prime95 v26 and the temperatures are so much better with this version :-D So if this is the reference that all others refer to, than im alright with the temps now. Around 47° for the CPU readout and a maximum of 60° for the core temps.

Thanks again