how do I reproduce it?

Just having render distance of about ~12 and try to play, occassionaly happens with lower distances too, after a few minutes

The game is unplayable, I'm having lags in single player game (digg blocks, and they reappear, and then disappear after few seconds), frame rate of 20fps (this is a shame with this gpu!) and random freezes

Similiar things happen with previous versions, like 1.7.4 / 1.7.2, but it also gives GL_ERROR: OUT OF MEMORY all the time and game freezes

I reported it previously, but some retard closed my ticket with a reason "modified client" even though it was stated that it is vanilla. So I say it again, it is vanilla client without any modifications.