i dont see it as dangerous, as long as you cool it properly. i've never had a card give up on me or loose pic quality cause of me OC'in it, and i leave the card pretty close to its limits when i finally get it stabel. i had a tnt2m64 OC'ed to the very max (hehe, about 175core and 200 mem i think, cant remember though :] ) for a long time and it never gave up on me. It all really depends on what you want. i usally ugrade every year or so, so i dont really need my gf3 to last for the duration of its 4 year warrenty(sp)