GPU Block Corrosion

[AbsoluteZero951]

This is a continuation of the Corrosion investigation that I started in a previous topic here  https://linustechtips.com/main/topic/778170-cpu-block-corrosion/#comment-9816235.

Upon removing the water blocks from the cards and opening them I was greeted by the purple corrosion inside the blocks pictured below. The worse one was the top card and the other the bottom, both linked by EKs Parallel connector. The corrosion in the top block, in particular, is much more severe than the CPU block was and further leads me to believe that it was due to the fact that I did not acid clean the radiators when first building the loop, but am unsure as to that could cause corrosion to this degree. I have since used the blitz cleaning acid on the radiators and had the fluid pictured below blue from the copper, but with little flux that came out of them, with the worst of it being from the Phobya Radiator. Additionally, the GPUs were directly after the Phobya, leading me to suspect the radiator. It has also discovered that I made a mistake in the coolant choice (Mayhems Pastel Extreme), as it was not supposed to be used with PETG, but don't believe that is the cause of the corrosion. Any insight would be greatly appreciated as I'm trying to figure out what went wrong here so It does not happen again and so I know what I need to rebuild my loop, as I have already gotten a new replacement CPU plate, and was thinking about replacing the Phobya radiator all together and not bother with it despite having blitzed it. 

 

Parts in Loop in order:

 

EKWB D5 Pump => Phobya G-Changer 360 => EK GPU Blocks x2 in Parrallel => XSPC AX480 => EK Supremacy EVO => EK XRES => back to Pump

 

Fittings where Primochill Revolvers and Tubing Primochill PETG 1/2 OD

 

Coolant was Mayhems Pastel Extreme White diluted to about 3 liters.

 

Other Parts: Bitspower Ball valve, Bitspower 90 rotary.

[W-L]

6 minutes ago, AbsoluteZero951 said:

-SNIP-

That's unfortunate to hear, while the block itself will run just fine as it performance wise aesthetically it's not as appealing. Were you able to test the old fluid for the PH to see if it went acidic?

[AbsoluteZero951]

2 minutes ago, W-L said:

That's unfortunate to hear, while the block itself will run just fine as it performance wise aesthetically it's not as appealing. Were you able to test the old fluid for the PH to see if it went acidic?

Unfortunately, I had already dumped the fluid before disassembling the loop as It was drained for transport so I have no way the know if it was the fluid that went acidic. I know really wish that I had kept the fluid until I had the loop disassembled. The performance of all the blocks was fine so I never suspected anything was wrong. It's not a huge deal as was planning on upgrading to a new GPU or two but would really like to make sure I don't repeat myself with new components. Would you recommend just avoiding the Phobya radiator as due to the fact that the corrosion was worse in the GPUs than in the CPU and the reservoir plugs where restive unaffected being farthest away from it, I'm fairly confident in that whatever happened it was due to the Phobya. Was planning on replacing it with a EKWB XE 360.

[W-L]

1 minute ago, AbsoluteZero951 said:

Unfortunately, I had already dumped the fluid before disassembling the loop as It was drained for transport so I have no way the know if it was the fluid that went acidic. I know really wish that I had kept the fluid until I had the loop disassembled. The performance of all the blocks was fine so I never suspected anything was wrong. It's not a huge deal as was planning on upgrading to a new GPU or two but would really like to make sure I don't repeat myself with new components. Would you recommend just avoiding the Phobya radiator as due to the fact that the corrosion was worse in the GPUs than in the CPU and the reservoir plugs where restive unaffected being farthest away from it, I'm fairly confident in that whatever happened it was due to the Phobya. Was planning on replacing it with a EKWB XE 360.

If they weren't cleaned very well from the looks of things it's very possible the flux from it down stream deposited it onto the blocks and fittings in that area. I would keep a very close eye on the new loop and periodically check the loop's PH every month or two to see if it has varied a lot, most loops should stay PH just slightly basic or barely PH neutral.

 

One thing that could have accelerate the cause though was the pastel extreme as I have found out recently the fluid is barely acidic due to the nature of the ethylene glycol base which is also why it was not recommended for PETG as it tended to dry out the plastic or crack it in long term use or high concentration. 

[AbsoluteZero951]

4 minutes ago, W-L said:

If they weren't cleaned very well from the looks of things it's very possible the flux from it down stream deposited it onto the blocks and fittings in that area. I would keep a very close eye on the new loop and periodically check the loop's PH every month or two to see if it has varied a lot, most loops should stay PH just slightly basic or barely PH neutral.

 

One thing that could have accelerate the cause though was the pastel extreme as I have found out recently the fluid is barely acidic due to the nature of the ethylene glycol base which is also why it was not recommended for PETG as it tended to dry out the plastic or crack it in long term use or high concentration. 

Thank you for the advice, I'll make sure to do the monthly checks, and hopefully having acid cleaned the rads this time and using proper coolant I can avoid ever doing this again.

[W-L]

1 minute ago, AbsoluteZero951 said:

Thank you for the advice, I'll make sure to do the monthly checks, and hopefully having acid cleaned the rads this time and using proper coolant I can avoid ever doing this again.

Yeah I've got to say a bit of an odd situation that I haven't seen before, maybe @EK Luc and @EK_Derick may be able to shine some more light on this as they probably have encountered this situation. 

[AbsoluteZero951]

4 minutes ago, W-L said:

Yeah I've got to say a bit of an odd situation that I haven't seen before, maybe @EK Luc and @EK_Derick may be able to shine some more light on this as they probably have encountered this situation. 

It's still got me a bit puzzled as well, due to its extent and the color and was thinking about reaching out to Mayhems as well to see if I could gain any more insight into the Pastel and how it might react with the PETG besides causing it to become brittle, crack, etc. 

[W-L]

Just now, AbsoluteZero951 said:

It's still got me a bit puzzled as well, due to its extent and the color and was thinking about reaching out to Mayhems as well to see if I could gain any more insight into the Pastel and how it might react with the PETG besides causing it to become brittle, crack, etc. 

Doesn't hurt to give it a go they might be able to provide some insight into it. The PETG from my knowledge only reacts with the Pastel Extreme due to the base chemical (ethylene glycol) and it being slightly acidic which I didn't know about until recently to be a result of the issue. 

[EK Luc]

12 hours ago, W-L said:

Yeah I've got to say a bit of an odd situation that I haven't seen before, maybe @EK Luc and @EK_Derick may be able to shine some more light on this as they probably have encountered this situation. 

 

12 hours ago, AbsoluteZero951 said:

It's still got me a bit puzzled as well, due to its extent and the color and was thinking about reaching out to Mayhems as well to see if I could gain any more insight into the Pastel and how it might react with the PETG besides causing it to become brittle, crack, etc. 

 

I must admit that I've never seen so much detoriation or residue build up in a block in such a small period of time!

 

[AbsoluteZero951]

13 hours ago, EK Luc said:

 

 

I must admit that I've never seen so much detoriation or residue build up in a block in such a small period of time!

 

What would you recommend to do with the blocks, try to clean them and see how well the cleanup, or leave them alone so that if I need send them in to EK and/or Mayhems to see if what happened here can be figured out so that it doesn't happen to anyone else in the future.

[EK Luc]

Since you took pictures of the damage, it's fine.  From there I would go and clean them.