[Cooling] x41 misbehaving? High Core/Water Delta T

[TehPenguin]

I use the x41 to cool my 1080ti for about 10 months now. It worked great up till about 2 months ago. I have a push-pull setup with both fans at around 8-900 RPM.

The first 8 months the water temps were 3-4 degrees lower than core temp and the performance was great. Now the disparity is as high as 15 degrees! So the heat does not get transported obviously. First I thought the liquid metal degraded so I cleaned everything up and replaced it with a healthy dose of MX-4 from Arctic Cooling, non conductive. Nothing changed. Even if not as high performing as liquid metal I think it should perform better than that. The performance is identical to before.

What can I try next before sending the unit back?

 

[Eximo]

My usual first recommendation is take the cooler out and rotate it in all directions, and power the pump. Occasionally air bubbles will get stuck in inconvenient places you want to get them in the small reservoir in the radiator. Changing the orientation might work as well, make sure the end cap away from the tubes is as high as possible. You can also try squishing the tubes a little to force things through.

It may have evaporated out enough liquid to need topping off as well. GPUs pump out a lot of heat and if you kept the liquid temperature high for long periods its vapor pressure can force it out through the rubber tubes. (They give ratings on hours of use usually, if you exceed that, it will slowly dry out)

Check the seals, particularly where the tubes go into the pump/chiller, you might have a very slow leak.

Liquid metal was a little silly on a GPU, that is more for CPUs to go under the heat spreader. GPUs are direct die cooling with a large surface area already.

 

[TehPenguin]

Yeah, the liquid metal was more for the fun of doing it. I did what you told me - unscrewed the radiator, rotated it a bit and gave it a few little shakes in hopes to release stuck air bubbles. I sadly cannot mount it differently because my case won't allow it. Sadly, no difference.