Concerned over current fan configuration

[Bluuz]

In my current rig, I'm using 2 bitfenix spectre pro 140mm as front intakes, 1 corsair quiet af 120mm as a bottom intake, and a corsair h80 with two noctua f12 as exhaust; all inside a fractal arc midi r2.

The problem is that when I run intensive applications, my graphics card gets hot (up to mid 70 C). I neglected from using another fan as a top exhaust because the dust proof cover seems to block a lot of the airflow. With my cpu cooler being also the only exhaust, this leads my cpu to also get warmer too, which is especially noticeable when I quit an application and it takes a few minutes for the heat to dissipate and the entire system to return to idle temperatures. Is this a cause for concern? Should I leave things the way they are or should I perhaps add an exhaust on the top?

[Samskip]

Mid 70's for a graphicscard are normal temps, no need to worry about that. You could use  a fan for the top exhaust but you wouldn't have as much positive air pressure.

Just remove the dust cover and add a top exhaust (if you have a spare fan) and see if there it makes any difference in temps.

[Morfy]

Just remove the noise-proof material, and let it radiate (the heat).

[Bluuz]

Another reason I left the dust cover is...well it prevents dust from getting in, and it has been doing a great job so far.