AIO Corrosion

[Brisdon]

So I've had an Corsair H75 for 4 to 5 years and during my anual pc cleanup I noticed a wierd coloration on the thermal paste and copper plate that makes contact whith the processor. I was wondering if that is a sign os corrosion and if so if I shuld be worried.

(sorry for any english errors, it's not my native language)

[TempestCatto]

Personally, other than the paste being kinda dry looking, the only thing I see here is just the copper colour wearing off. AIO's have all sorts of goodies in the liquid to prevent corrosion. For the most part, any AIO should last as long as its pump. The thing to check is if it still cools your CPU the way it should, or if it's starts getting hot after some time (with load).

[Mick Naughty]

Don’t see any corrosion. Don’t see any real issues. New paste should do its job, or a light wet sand in both directions if you feed the need and have the materials. 

[Anonymous12]

I don't see any corrosion at all, and all AIO has corossion prevention goodies.

[asand1]

That's called tarnish. Copper turns color when exposed to other compounds such as oxygen, salt, etc. If it bothers you, you can polish it with some Brasso. Tarnish won't affect your cooling and has nothing to do with the coolant inside.