only what is available in the gui. I think it was 196M ? I don't have it running right now, but from what I could tell from the firmware upgrade there were three settings. The middle being default. The lowest setting had no effect. I ran it again today after doing a manual reset of it from the led panel and the same thing happens. Does the S2 run at 1000W consistently or is even my first watt meter showing 1090 too high for the miner to be at. Maybe it is the PSU, something with it. I looked at the cables and such and couldn't find anything unusual. There was some wear on the fabric covering the large on power cable, but that was from being bent. It's got to be something with the PSU or the controller firmware/board at the base and/or the beaglebone (i think that is what it is).
At this point I would think it's the psu... mine died after the 2 months and it would also run for a few minutes and shut off (I don't have a killawatt). I had it replaced by Bitmain and it's been running perfectly since.
You could try removing one or two of the boards and see how well it runs like that.... that's what I did while waiting for my replacement psu.