That's weird, I tried lowering my memory clock to 900 (minimum) and the performance lowered 10-20 mh / sec. As soon as I put them back up, they returned to what they previously were.
See my post above.
Fiddle with it - for whatever odd reason, one of my cards seems to have "sweet spots" (I'm sure yours does, too).
Here are some examples from one of my cards -
900 CPU, 220 Memory - 5 MHs more than if I put the memory clock at 150 *or* 1125.
1000 CPU, 300 Memory - 15 MHs more than if I put the memory clock at 1125 or 200.
1025 CPU, 200 Memory - any other settings crashes the card
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