Quote from: RadekG2 on June 20, 2018, 09:17:51 PM

Based on my experiences with Antminer D3, some boards works better at higher frequency at the same voltage level. The correct frequency was only one unique frequency. Lower didn't work and higher didn't work also. It is probably because of chained chips are dividing voltage between each chip group a bit different at each frequency.

Check kernel log for "setting working voltage" where you will see which working voltage it applies with autofreq or with fixed voltage. Autofreq boards has different voltage for each board while fixed freq sets the same voltage for all boards. I was shocked, that at 600MHz fixed firmware applied 9.3V for the chain and at 650MHz it undervolted to 8.8V.

This Is 650 Fixed Firware

Code:

Fix freq=662 Chain[5] voltage_pic=108 value=880
Fix freq=662 Chain[6] voltage_pic=108 value=880
Fix freq=662 Chain[7] voltage_pic=108 value=880
set_reset_allhashboard = 0x0000ffff
set_reset_allhashboard = 0x00000000
Chain[J6] has 63 asic
Chain[J7] has 63 asic
Chain[J8] has 63 asic
Chain[J6] has no freq in PIC, set default freq=662M
Chain[J6] has no core num in PIC
Chain[J7] has no freq in PIC, set default freq=662M
Chain[J7] has no core num in PIC
Chain[J8] has no freq in PIC, set default freq=662M

Chain[J6] set working voltage=880 [108]
Chain[J7] set working voltage=880 [108]
Chain[J8] set working voltage=880 [108]

Is that It? 880 8.8V? So maybe better running the 600M Fixed Firmware and adjusting that to 662/668Mhz etc