Riser: try to buy risers with 6-pin PCIe power connector and 4 capacitors. Throw away the SATA or Molex adaptor power cable that comes with the riser and use this splitter cable to power both the gpu… ((more))
For folks still experiencing this issue I would suggest two areas of concentration:
1. If you still have ANY overclocking on the cards that are inoperable remove it back to box stock.
2. Power, power… ((more))
The Claymore developer says in his README if you don't want to pay his fee you have two choices: 1. Turn off dev fee and suffer a approx. reduction in hashing of 5%, or 2. Use another miner.
Come o… ((more))