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It is known that epsi-noisy gates with two inputs are universal for arbitrary computation (i.e., can compute any function with bounded error), if all gates fail independently with probability epsi and epsi < beta2 = (3 - radic7)/4 ap 8.856%. In this paper, it is shown that this bound is tight for formulas, by proving that gates with two inputs, in which each gate fails with probability at least beta2 cannot be universal. Hence, there is a threshold on the tolerable noise for formulas with two-input gates and it is beta2. It is conjectured that the same threshold also holds for circuits.