Discussion 2nd D5 pump died

[thilanliyan]

I've had a 2nd D5 pump die on me in the space of 4 yrs 🙁
Both lasted about 2 yrs (both vario versions).
Googling around, it seems it's better to run the pump at 50%+ power. I didn't make this connection until the 2nd one failed. Both of these pumps were mounted in a XSPC 5.25 bay-res. I was running them at low speed because they were just too noisy otherwise.

I had been running around 20-30%. Both times the impeller ended up contacting the curved surface on the inside of the pump, I'm guessing because the bearing seat surface wore down (not sure how that happens when running lower speed) and the impeller was no longer centered. I was running straight distilled water + silver kill coil (been doing that for the past 20+ yrs on all my builds). CPU block is full copper (no nickel plating) and rad is xspc rx240 (brass I think).

I have another D5 (pwm) running at 75% for 3+ yrs now and that's been fine. And another D5 (vario) I had running continuously for 5+ yrs at around 70% and that was also fine.

Anyway, just wanted to post this in case it is useful for others.

As D5 PWM pumps are harder to find in Canada I ended up purchasing an Alphacool APEX VPP pump (the ones that's different to D5s)...not a lot of long term reliability data on those I think but I'm willing to give it a go since it's supposedly much quieter than a regular D5. Will update with impressions once I install it.

 

[sdifox]

Or switch back to fans

 

[thilanliyan]

Or switch back to fans

I was actually planning on doing that...until I realized my custom wood case won't really allow me to put any decent air cooler on there (if any at all). I built this case around watercooling only, it's tall and narrow, so I either go AIO or stick with the custom watercooling. I'm going to give it one more shot with the Apex VPP pump and if that ends up failing I'm going to transform the case somehow to do air cooling.

 

[sdifox]

Or cut a hole xd

 

[aigomorla]

what company D5's are you using?
Were they different companies?

Its very unsettling how you lost 2 d5's as those are seriously tanks.

I know there is a lot of fake D5's running in the market too. Did it have the silver for the impeller housing and impeller or was any of it plastic? Meaning was the round bottom portion made of metal?
It should look like this:

Real D5

Fake D5:



Did you check the ceramic tip on the impeller housing to see if it cracked or broke?

Im just amazed you burnt though 2... i haven't even burnt though 2 ddc's and those are a lot more fragile them D5's. D5's are like the Tacoma trucks, while a DDC would be like a Supra.

Or switch back to fans

NEVER!

Once u watercooled a GPU, you will NEVER go back, even tho its a hassle.
Well i might next time as no RMA service from ANY of the GPU maker now that allows removal of stock heat sink, and seems like they are more built like cotton candy now, so they break very easily.

But still.... watching your 4090 not break 60C under heavy load and your graphics ram sitting at a cool 40C, is enough merit for me to go though that hassle.
When i see a loaded AIR GPU, i cringe... i know its safe, but i bet you my 4090 will probably easily last me until the AI's farms start dumping there 48GB RTX PRO's, or until the 6090 get launched.

 

[thilanliyan]

what company D5's are you using?
Were they different companies?

Its very unsettling how you lost 2 d5's as those are seriously tanks.

I know there is a lot of fake D5's running in the market too. Did it have the silver for the impeller housing and impeller or was any of it plastic? Meaning was the round bottom portion made of metal?
It should look like this:

One was Watercool (latest one that failed) and the other was Darkside (rebranded standard D5 vario, Canadian store Dazmode). Both were real D5s. Both impeller and housing are stainless steel, definitely not like the fake D5s. When the darkside one failed I thought maybe it was like "B" stock or something that they rebranded, so chalked it up to luck, but when the Watercool one failed I figured something was wrong with the way I was running it. It was 2 failures in the space of 4 yrs btw, edited my OP, still too quickly imo since I've had other ones last much longer (running them at higher speed).

Ceramic tip is intact and round. It's the plastic area of the bearing seat on the impeller that has worn down (on one side only), which then puts the impeller off center, which then contacted the housing.

I'm guessing that the low speed coupled with the pump being in a horizontal orientation (in the XPSC bay-res) caused the issue. Meaning I think if the pump was oriented vertically it would probably last longer. Maybe running them at higher speed equals more centrifugal ("outward") force, "lessening" the downward force due to gravity (when running horizontally) resulting in less wear of the bearing seat...? I dunno lol.

 

[thilanliyan]

Got the Apex VPP pump.
Looks decently built on first impression, other than being hard plastic instead of metal like the D5, but maybe that makes them easier to balance.

It's much quieter than the D5 for sure (at least the ones I've had mounted to the XSPC bay-res). Running it at 75% PWM and can just barely hear it.

Let's hope this one lasts lol.