Oh didnt know there is thermal paste for GPUs as well as CPUs. I am not sure if i would know how and where to add it on. As for ventilation computer box has actually intake/exhaust ventilation sucking air at bottom and then exhausting it on upside creating airflow trough cards, but it doesnt help much since GPU temp goes straight to 95 on first minute of mining.
Yep, both cpu's and gpu's have thermal paste on their chips.
You can use this to see how to take the card apart and clean/repaste it
https://www.youtube.com/watch?v=XvD1s83u_hQThen just go in reverse order to put it back together.