This should be handy for all hybrid cooled GPU users, not much information about that on the Web.
So, Im just finished servicing an AIO on my EVGA GTX TITAN X Hybrid 12G-P4-1999-KR
It was overheating to 83 degrees after a years, and it is back to 55-60 under stress testing now.
I was looking to buy a new hybrid cooler, bracket, air cooler, tried push n pull, different positions of the radiator inside my tower... waste of time, save your money.
The solution is very easy and cheap.
All you have to do, unscrew a coldplate only, 8 nuts inside radius, dont touch the nuts on outside radius, they hold a mount plate and the whole block together.
Drain old coolant, fill, shake and rinse a radiator a couple times with a coolant, or you can even buy a special automotive coolant system cleaner, to make sure no more dirt is coming out.
Clean microchannels on cold plate with an old teethbrush, or anything you figure out, some acid might be handy. Lots of debree was there, plugged everything.
Fill radiator with a coolant ( Just keep a water block on top of the radiator, and shake a radiator to make sure air come out of radiator as much as possible while you filling) and screw everything back together.
At the end, dont forget to remove the plastic cover on top and dry electronic components inside with a hairdryer:)
Used the cheapest 50/50 automotive coolant from wallmart for 10$. Factory fill 100ml, I filled as much as possible, around 120-140ml i guess, everything works perfect.
Good luck guys :)