Corrosion concerns

[straxxus]

Recently I decided to add a GPU block to my custom loop (specs below), but I realized the block I got may be a different metal than my cpu block. I purchased the bitspower NGTX980MG block for my main gtx 980 gaming. My current loop specs are: cpu block- ek supremacy MX
rads- 1x Black Ice Nemesis 240GTS
1x Black Ice Nemesis 140GTS
Pump/res- X2O 420 Single Bayres/Pump
Reservoir
And a Monsoon Silver Bullet Antimicrobial G1/4 Plug for a kill coil.
I'm currently running standard distilled water and haven't observed any corrosion on my cpu block after the ~1 year I've had it for. My concern is that my GPU block isnt copper and it might corrode something. Bitspowers website doesn't say much about the block but it looks like it's silver plated nickel or just nickel. I was wondering if I would want to get a corrosion inhibitor?

 

[Lochekey]

The Bitspower website says it is nickel plated. You will be fine with just the distilled water and kill coil. Nickel plays nicely with copper and silver so you should not have corrosion issues.

 

[straxxus]

Well that was quick, thanks for the reply! As a semi-related question, does putting Tim on the GPU vrms actually improve cooling at all? I saw something about it in a guide I was reading.

 

[Lochekey]

I do not have any good testing to definitively say one way or another. I know that replacing the pads with strictly paste will sometimes produce worse results because the block is not cut for direct contact onto the vrms.

I use the specified thickness of pad that the manufacturer recommend and then put a little Tim on either side of the pad to fill in the rough surface of the pad. As I said I cannot verify that this gives me better temps but it does make me feel better.

As an aside there are some factory water cooled cards that apparently come with TIM applied to the pads as well.

 

[straxxus]

Cool, I'll probably throw some on there since I have a giant tube of arctic ceramique. Thanks for all your help!

 

[GTXJackBauer]

After a long time, I'll reapply TIM to my GPUs. Maybe after 2-3 years but most of the time, I do it once in the beginning and leave it alone.

Are you having issues with your GPU temps? The Bitspower GPU blocks AFAIK are fairly restrictive. They seem to do poorly in most tests i've seen. Anywhere from 5c-8c from the best performer leaving it usually at the bottom of the list for worst. Regardless, its still a waterblock and will get the job done.

MX4 is the choice for many around here for TIM. You only need to put it on the actual CPU and GPU chips. Just leave the other parts with the thermal pads alone.

 

[straxxus]

Im not having temperature issues; this is the first time I've water-cooled a GPU so I just wanted to cover my bases.
Also, according to this article: http://www.xtremerigs.net/2015/04/07/gtx-980-water-block-round-up/ the bitspower block isnt particularly restrictive, and also doesn't significantly effect temperature compared to most of the other blocks. So I'm not really worried.

 

[Silver Surfer]

does putting Tim on the GPU vrms actually improve cooling at all? I saw something about it in a guide I was reading.

It does if you can actually do it, it will require on your part test fitting the water block to the GPU and inspecting the TIM footprint on the memory chips and VR.

Usually the VRs sit lower and require the thicker padding to make contact, but that is in a perfect GPU manufacturing of the graphics card, in some situations you can get a fit so good that TIM can be used for all but that depends on the manufacturing quality of the water block and what it's design fit tolerances actually are.

That is why it is imperative to test fit and see what the thermal footprint looks like on the contacting surfaces before sealing it all up and assuming you are OK and throwing power to it.