Originally Posted by thechosenwon
I should check back here more often, your explanation is not exactly correct.
Easiest way to explain ASIC and how it relates to you guys is that it is a measurement of the quality of the gpu and how well it can scale at a set baseline voltage.
Higher asic means it needs less voltage for XXX clock. Lower asic means it will need more voltage for XXX clock.
Prior to maxwell, ASIC HAD LESS meaning or I should say was less significant
because you got a lot of voltage scaling out of Kepler. You could take a lower asic 780kpti card for example, give it lots of volts and it can hit the same clocks as a higher asic counterpart running less voltage but clocking higher. On Maxwell, we do not have this luxury of running 1.4v+ on the gpus using air/water cooling
. This means that ASIC is more relevant because "typically and in most cases" a higher ASIC card will get you more clocks with the lowest possible voltage at the end of the day considering the voltage limits on Maxwell. For the sole reason of not being able to add much voltage on air/water with maxwell, ASIC becomes more relevant this gen, not the other way around.
If you take ten pieces 80% ASIC and 10 pieces of 70% ASIC, and see how high each one clocks with min def voltage for KP980ti cards of 1.16v under 3d load, you will see the higher ASIC cards clocking the highest. There are always exceptions ofc, so not all cards will fall in line like that. Which brings us to the next part, leakage.
ASIC does not accurately reflect leakage unfortunately and THIS is the lottery part of the equation and what can cause a high asic card to "underperform" to expectations. HIGHER ASIC DOES NOT EQUAL LOWER LEAKAGE
, it is the opposite. Higher ASIC has higher leakage PERIOD. Leakage and gpu scalability/headroom/ASIC VALUE scale linearly together. Lowest ASIC cards have lowest leakage, this is one reason why on Kepler you were able to increase the voltage on a low ASIC part so much and get good scaling on air water, because they had lowest leakage. Can a lower asic card clock higher than a higher asic card, YES! It is because of leakage values and all cards are different. The "lottery" is the LEAKAGE. Some high asic gpus have insane leakage numbers, This is THE SOLE reason why a high ASIC card may fall short on air/water. So much nonsense about ASIC on the net since 980KPti launched, what I explained is the real deal. Hope it helps you to understand more.
Originally Posted by looniam
AISC represents how much "leakage" a chip has.
higher ASIC is lower leakage and won't need as much voltage to get the same clock speed as a chip with a lower ASIC.
prior to maxwell, ASIC had more meaning but now plays a much smaller role in OCing. your 75% ASIC card will boost slightly higher out of the box (w/default voltage) than a 72% ASIC card. but how much more you get out of it is still the silicone lottery (as usual) and what kind of temps its dealing with - lower=better.