75% of 9 = ... 6.75
so obviously if you run it at 8 and only get less than 15% you are ahead
Exactly. I should get cgminer running so I can see how many cores are running on each CPU, and if that changes by my moving the diagnostic level from 10 to 1. Right now I backed out my 8 change yesterday to 7, left the diagnostics set to low, and am getting 4% failures on the bad chip instead of the 2% before. So I might have enabled another core that is throwing 2% errors overall on the chip.
The trick with running faster is it burns more heat, it seems to be going up exponentially and not linerally as I clock up, more heat=more wear=more power (which is a hill of beans right now, even with the laptop the whole shooting match only pulls 40 watts).
Next up is to try powering the system off a 12 volt battery to see if a perfectly smooth power input reduces errors. If some of the error is caused by instabilities due to the cheap-o-power supply, clean DC might mean more cores to bear which would mean more $$$$
C