I've added to the cgminer API the ability to change the Core Volts and Frequency whenever you like
So basically java API "ascset|0,mv,1280" will set the first ASIC to 1280mV
and java API "ascset|0,freq,400" will set the frequency to 400Mhz and adjust the timeout to the required value
(for 400 it is 31)
So basically the same as when you start cgminer, but you can now change it on the fly.
Default limits are 1000-1310 - I've no idea if 1310 will kill it - but if you feel the urge to go higher than 1310 you'll have to edit the constant and recompile
Frequency limit is the same as before 256-450
I've run an almost 13hr run at 400Mhz and got:
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(5s):7.590G (avg):7.774Gh/s | A:81228 R:409 HW:1183 WU:110.1/m
ST: 2 SS: 25 NB: 101 LW: 95546 GF: 1 RF: 0
Connected to au.ozco.in diff 8 with stratum as user ***
Block: 0048594bd9a0cb3e... Diff:37.4M Started: [14:58:34] Best share: 42.8K
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[P]ool management [S]ettings [D]isplay options [Q]uit
BTB 0: 46/ 46C 1221mV | 7.558G/7.774Gh/s | A:81228 R:408 HW:1183 WU:110.1/m
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[2013-08-08 15:05:16] Accepted 051dac50 Diff 50/8 BTB 0 pool 0
WU:110.1 = 7.88GH/s
Error rate is 1.4%
I did try 450MHz for a short while before I started this long run and got about 50% errors.
Also I set the voltage to 1280 and it didn't blow up but I changed it back straight away
The temp of 46C+ seems to be the relevant number determining the error rate
I'll do some voltage/MHz adjustments later to see if I can speed things up (without destroying it or getting too many errors)