I still remember a GeForce MX440 I bought once. It was stuttering as hell in games. Overclocked it for better performance. Still stuttering.

Looked at it and two of the plastic clips (yeap, no screws back then lol) holding the heatsink+fan were snapped so the heatsink wasn't even touching the die... WTF!

That was pretty hilarious. It worked fine for years after I fixed it, long enough for caps to blow and be replaced.

Basically, they're fucking sturdy.