This will be a very long post but I am facing some very strange results from my watercooling loop. This is my first watercooling loop so I am just going to show you the data I gathered and please tell me if you see anything wrong.
My main issue is that I am seeing very underwhelming cooling performance for my CPU while my GPU has quite good results.
My Setup: CPU: Intel i5 8600K Mobo: MSI Z370 Krait Gaming RAM: 16 GB DDR4 3000 MHZ G.Skill Dual Channel GPU: Asus RX Vega 56 Strix Gaming OC Sound card: Asus Xonar Strix Soar SSD: Samsung 960 PRO, Intel 545s, Intel 660p (all M.2) Case: Cooler Master Mastercase Pro 5 Fans: 6X Noctua NF-F12 chromax PSU: Corsair RM650X
- CPU Block: EK Supremacy MX, used with Noctua thermal paste (new tube)
- GPU Block: EK-FC Radeon Vega Strix – Nickel, used with Noctua thermal paste and Thermal Grizzly pads
- Rads: EK-Coolstream SE 240 & EK-Coolstream Classic PE 360
- Pump combo: EK-XRES 100 Revo D5 PWM
- Tubes: EK-Duraclear 9.5/12.7
- Coolant: EK-Cryofuel Clear
- Fittings: various EK-ACF 10/13mm
Please see below the temps I recorded (all after 15 mins full stress test on CPU & GPU, in 25C ambient):
Stock CPU + Stock GPU:
- Fans @ 40% & Pump @ 40%: CPU - 75; GPU - 50
- Fans @ 100% & Pump @ 40%: CPU - 66; GPU - 41
- Fans @ 100% & Pump @ 100%: CPU - 66; GPU - 38
5Ghz OC CPU + Stock GPU:
- Fans @ 40% & Pump @ 40%: CPU - 80; GPU - 52
- Fans @ 100% & Pump @ 40%: CPU - 75; GPU - 38
- Fans @ 100% & Pump @ 100%: CPU - 75; GPU - 38
For reference, while I was using air cooling, the 5 Ghz OC CPU temp was 80C using Noctua NH-D15 with 3X 140mm fans. Also, for my Strix GPU, max air cooled temp was 81C.
Idle temps are 33C for the CPU and 28C for the GPU.
2 thing I find really strange:
- The difference between the OC temps on the Noctua NH-D14 and the watercooling loop is very small, was really expecting a big difference. Is is even stranger since the GPU lost 35-40 degrees going from air to watercooling.
- In the same loop, I observe a 25C difference between CPU & GPU, this dose not seem normal to me
I’ve done the classic troubleshooting steps:
- Removing the CPU block and making sure I have good contact and good spreading of the thermal paste
- Only using a pee size ball of thermal paste in the middle of the CPU
- Removing all air pockets from the loop
- I even changed coolant, thinking I had a bad batch
I don't have a temperature sensor for the cooling liquid but I can confirm that the tubes are hot to the touch under full stress tests, no idea if it is normal and the 3 exhaust fans are absolutely vomiting hot air thought the top and back!
Please tell me if I am doing something wrong or if I am interpreting the data incorrectly. I know the GPU is in a X8 slot but from my testing and the results I found online, I can find no difference in performance for my GPU (same FPS in games, same results in benchmarks).
P.S.: sorry for the shit photos, literally took them at night with the phone under the desk.