Hello,
Install montables and run the query down to identify the command runing and using 100% of the cpu.
select sp.ipaddr,
s.SPID,
s.CpuTime,
s.PhysicalReads,
s.PacketsSent,
s.PacketsReceived,
t.LineNumber,
t.SQLText
from master..monProcessStatement s,
master..monProcessSQLText t,
master..sysprocesses sp
where s.SPID=t.SPID
and sp.spid=s.SPID
order by s.CpuTime desc