88c on a liquid cooled GPU is not normal, if it were to be a founders edition or an EVGA FTW card then that’s “ok” but still too hot for most cards.
Check your water pump that is flowming water to your GPU, or check the water block to see that water is flowing through the block, and make sure it’s screwed down evenly cause if not it can cause many hot spots within the GPU.
Also do not run your GPU for this long at that temp range you can cause further damage to the card and it can’t be fixed, like my 970 it died due to overheating.
Please make sure you check on your custom water loop, make sure all fittings are tight, make sure there is correct amount of water within the tank, make sure the pump is working as well, and again look at...