This paper summarizes the problems for the currently proposed hardware transactional memory system which supports context switch/migration, virtual memory paging, and system call issues. A new hardware transactional memory system called DTM is proposed. DTM performs transaction conflict detection through a separate protocol, which works in a similar way as the traditional directory based cache coherence protocol, but only operates on the transactional states. Test results show that DTM achieves improvement in design complexity, scalability and performance issues.