Some strange things are happening:
008-0: ztex_ufm1_15y1-04A39E1212-1: f=220.00MHz, errorRate=0.51%, maxErrorRate=1.10%, hashRate=218.9MH/s, T=46.4°C, submitted 15 new nonces, luckFactor=1.05
008-0: ztex_ufm1_15y1-04A39E1212-2: f=216.00MHz, errorRate=1.21%, maxErrorRate=1.81%, hashRate=213.4MH/s, T=45.8°C, submitted 15 new nonces, luckFactor=1.06
008-0: ztex_ufm1_15y1-04A39E1212-3: f=224.00MHz, errorRate=0.00%, maxErrorRate=0.00%, hashRate=224.0MH/s, T=52.2°C, submitted 12 new nonces, luckFactor=0.87
008-0: ztex_ufm1_15y1-04A39E1212-4: f=220.00MHz, errorRate=0.00%, maxErrorRate=0.00%, hashRate=220.0MH/s, T=45.1°C, submitted 11 new nonces, luckFactor=0.93
There isn't anything strange:
> 1. Chip 3 is running with 8 degrees more then chip 4 - something to worry about?
Accuracy is about 5°C A difference of 8°C beetween hottest and coldes temperature is normal.
> 2. Chip2 is producing more errors then the other three, which results to a lower frequency and lower hashrate (of course).
Not all FPGA achieve the same performance. Values can be found in the inital posting of this thread.
Device Enabled Status MHS av MHS 30s Accepted Rejected Hardware Errors Frequency
ZTX1a Y Alive 213.988 215.727 102 0 10 216.000
ZTX1b Y Alive 214.320 215.715 115 1 259 216.000
ZTX1c Y Alive 210.527 211.729 115 1 2 216.000
ZTX1d Y Alive 222.402 223.756 144 0 71 216.000
that is what I wanted to show you. .. it is for off with the hardware error rate.
I'm not involved in bfgminer and can say how these values are computed. But if you would downclock it, you probably see no hardware errors anymore.
Goal of mining software (at least BTCMiner) is to achieve maximum hash rate. And often you achieve a higher hash rate if you overclock and accept a few errors.