I bought a TITAN X Hybrid in late 2015. In the beginning the temperatures were amazing for such a silent card, maxing out in the 40s or 50s at full load. I recently checked again and it's getting up to around 80. Idle is 35. I cleaned the radiator and bumped up the fan to 100%, no difference. The radiator and exhaust air are still hot, but probably not as hot as before. What might be the problem?

It sounds like the pump may not be circulating the coolant properly. You can usually check this by:
 
A) Listening for the pump to be on. If you don't hear the pump running, double check that the hybrid cooler is connected to the card (header is located under the shroud so this may be a more advanced step for some users, but it's only a few screws so most should have no issues).
 
B) Feeling the hoses. One should be warmer than the other. If they're the same temp, then likely there is an issue.
 
If either of these cases points toward the pump then you can stop there and we'll probably need to start an RMA. If these seem fine then you'll want to continue to:
 
C) Reseat the waterblock and reapply thermal compound. Poor contact or heat transfer will significantly impact the cooler's performance.
 
At this point, if you're still pulling 80°C on a hybrid card it's probably time to submit a support ticket so we can get involved directly since you've pretty much exhausted your options without voiding the warranty. If you have any questions about the process please feel free to contact us anyways, and we can try to troubleshoot with you if you need the extra support.
 
We do have a youtube video for the process on our TEAMEVGA channel: https://www.youtube.com/watch?v=MepbdKc6m_s 
 
Or you can check out the installation guide for the Hybrid kit for a little more guidance here: http://www.evga.com/support/manuals/files/TITAN_X_HYBRID_Installation_Guide.pdf 
 

quatrix

Scarlet-Tech
Can you see if the pump is running properly?

How would I determine that?

Read the post directly above your question here. Garrett covered it very well. It sounds like your pump may be underperforming.

I bought the hybrid I have off of Amazon for over 50% off, brand new.

''To OP:
These pumps/radiators/fluid are usually only good for 3 years max, so it looks like you may be at the end of your cooler lifecycle (counting on the shelf also).
:(''
 
yup if your lucky it does  and evga don't offer any support or replacement parts [cooler/pump ]    just throe in trash and  buy another card  [preferably evga] LOL...... 
 
I hpor the 10 series guys look all these 900 failed hybrids over   and see  they may not have any replacement parts  when theres fail as well down the road  
 
like I said right now it seems that corsair deal is the only new option  to replace the pump  unit    cause it sure as heck aint EVGA .    your done for with them  on that
 
now I'm waiting to see how this guys RMA works out for him   If he posts back on what he ended up with from them
 
http://forums.evga.com/PC-is-Crashing-screens-go-blank-suspect-980ti-hybrid-m2595004.aspx
 
 don't seem like I would get any hopes up  for a direct new  replacement   maybe a  used referb or a gtx 1060 at best    is how I;m seeing it