AES-128 is encryption, not a hash. AES-128 will be broken when computers get enough compute power to calculate 2^127 keys (the brute force attack: after covering 50% of the keyspace).

Cryptographic hashes are prone to the birthday attack instead. MD5 hashes (128-bits) are broken when a computer has enough power to calculate 2^64 keys (birthday attack: they found a hash collision).