D5 pump pressure question

Sartsj · August 25, 2021

Recently I had my second D5 pump die (it rattled when I woke up in the morning, pc ran through the night), after having the same thing happen a few months ago. The first pump died pretty soon after expanding my loop from just cpu + slim 360 rad to cpu + gpu + 2 GTX 360 + the same slim 360. Back then I was worried but after asking some people online I didn't think too much of it.

I configured the pump in the bios to run at somewhere below 50% (possibly 30% even) speed normally. (honestly I'm not sure of the exact setting anymore, still have yet to install a new pump so I can't check)

It is configured to go up to 75% or so based on water temp.

Now that the second pump has also died in what seems like the same way, I am a bit worried that maybe I have a low flow rate due to pressure + pwm settings and that that is causing the pump to die, is that even possible? I know these things need water so that the pump bit doesn't scrape around in its socket, but is that also dependent on the flow rate?

Pumps that died have been one Alphacool VPP655 unit and this latest one a EKWB G2 unit. I have now ordered a EKWB G3 unit.

Forgot to add: Temps have always been fine, GPU (3080 FE) never goes above 50c. CPU (5950x) goes a bit higher under load i think but they're toasty boys anyway.

For Science! · August 25, 2021

33 minutes ago, Sartsj said:

Recently I had my second D5 pump die (it rattled when I woke up in the morning, pc ran through the night), after having the same thing happen a few months ago. The first pump died pretty soon after expanding my loop from just cpu + slim 360 rad to cpu + gpu + 2 GTX 360 + the same slim 360. Back then I was worried but after asking some people online I didn't think too much of it.

I configured the pump in the bios to run at somewhere below 50% (possibly 30% even) speed normally. (honestly I'm not sure of the exact setting anymore, still have yet to install a new pump so I can't check)

It is configured to go up to 75% or so based on water temp.

Now that the second pump has also died in what seems like the same way, I am a bit worried that maybe I have a low flow rate due to pressure + pwm settings and that that is causing the pump to die, is that even possible? I know these things need water so that the pump bit doesn't scrape around in its socket, but is that also dependent on the flow rate?

Pumps that died have been one Alphacool VPP655 unit and this latest one a EKWB G2 unit. I have now ordered a EKWB G3 unit.

Forgot to add: Temps have always been fine, GPU (3080 FE) never goes above 50c. CPU (5950x) goes a bit higher under load i think but they're toasty boys anyway.

Unlikely for the pump to die with this loop configuration and speed. It generates very little heat and is in itself liquid cooled. I have a more restrictive loop thats been running 24/7 since the pandemic began, and this pump has been in operation since 2017. D5's are very reliable so I'm surprised you had two die on you.

As a side note, I dont think it is so meaningful to ramp the pump speed with water temp, you should probably just set it to the max comfortable level and leave it be. A constant hum is less noticeable than one that changes its frequency with load.

Sartsj · August 25, 2021

6 minutes ago, For Science! said:

Unlikely for the pump to die with this loop configuration and speed. It generates very little heat and is in itself liquid cooled. I have a more restrictive loop thats been running 24/7 since the pandemic began, and this pump has been in operation since 2017. D5's are very reliable so I'm surprised you had two die on you.

As a side note, I dont think it is so meaningful to ramp the pump speed with water temp, you should probably just set it to the max comfortable level and leave it be. A constant hum is less noticeable than one that changes its frequency with load.

Ok, good to know! Thanks. Then I will go back to not worrying about it.

You're probably right about the pump speed settings, but honestly I doubt it ever speeds up already, because from the way I remember it i set it to not ramp up until 30c, and I don't remember the water ever getting that warm. I will probably take your advice after installing this new one and just setting one speed and make it as high as it can be for it to be not noticable, just to ease my mind.