I have one rig in my farm which keeps crashing every 3 hours or so.

Usually I can open up the log file and find out which particular GPU is causing issues, and rectify the problem without much headache.  But this time, i'm getting this message...

13:18:08:445   5ac   buf: {"id":4,"jsonrpc":"2.0","result":true}
13:18:08:445   5ac   parse packet: 38
13:18:08:445   5ac   ETH: Share accepted (47 ms)!
13:18:08:445   5ac   new buf size: 0
13:18:09:865   eb8   GPU0 t=70C fan=82%, GPU1 t=67C fan=78%, GPU2 t=65C fan=81%, GPU3 t=65C fan=74%, GPU4 t=71C fan=79%
13:18:09:865   eb8   em hbt: 0, fm hbt: 16,
13:18:09:865   eb8   watchdog - thread 0, hb time 250
13:18:09:865   eb8   watchdog - thread 1, hb time 32
13:18:09:865   eb8   watchdog - thread 2, hb time 32
13:18:09:865   eb8   watchdog - thread 3, hb time 19906
13:18:09:865   eb8   watchdog - thread 4, hb time 234
13:18:09:865   eb8   watchdog - thread 5, hb time 32
13:18:09:865   eb8   watchdog - thread 6, hb time 297
13:18:09:865   eb8   watchdog - thread 7, hb time 94
13:18:09:865   eb8   watchdog - thread 8, hb time 125
13:18:09:865   eb8   watchdog - thread 9, hb time 328
13:18:09:865   eb8   WATCHDOG: GPU error, you need to restart miner
13:18:09:865   eb8   Rebooting


Its not specifically telling me which GPU is having issues, although i'm assuming its whatever was working on "thread 3" - how can I find out which GPU is working on thread 3?  Claymore, please help!  This is driving me nuts.   This rig usually hangs after the "Rebooting" message.