Funny that on my windows 7 i can ran my bitmain u2 only on 1,8 with no hw errors, but on my apple mini mac i can run it at 2,2gh no problem and no errors.
Bitminter does not go higher than 2,2 i saw, astroid did but made hw errors with  2-2,4gh's. 
Astroid is for apple.

Windows 7 with asicminer u1 is good on 2 gh's and with hw errors on 2,1gh/s.

Soon i hope to order s1's and butterfly's the 50gh/s's ...

will see.

Me just updating for what i learned allready.