There are entrys in the windows 2008 r2 log
cissesrv - 24791
Array controller P420 located in server slot 2 has reported that its internal temperature has exceeded the preset limit of 65░C. The current temperature is 255░C as reported by sensor number 4. The controller may attempt to shut down power and/or spin down installed disk drives.
and
cissesrv - 24632
Array controller P420 located in server slot 2 has reported that its cache has been disabled.
Why cache is disables, btw it enables after reboot. And why 255 ?
Smart array P420
Firmware Version 3.42
ACU Version: 9.40.12.0