Hahah, then your i7 got less than a year left on its lifespan.

Do not underestimate the overheat, you might not know when, but anytime can be a breaking point.
@OP The Overclock will not break your GPU, but the heat (your Sensors might be inaccurate) or the overclock settings.
The most PGU breaking mis-configuration is the over-voltage setting, the GPU might be stable with a setting but, its down-insides has problems.