With rising capacities and higher accessing frequencies, highperformance DRAMs are providing increasing memory access bandwidth to the processors. However, the increasing DRAM performance comes with the price of higher power consumption and temperature in DRAM chips. Traditional low power approaches for DRAM systems focus on utilizing low power modes, which is not always suitable for high performance systems. Existing DRAM temperature management techniques, on the other hand, utilize generic temperature management methods inherited from those applied on processor cores. These methods reduce DRAM temperature by controlling the number of DRAM accesses, similar to throttling the processor core, which incurs significant performance penalty. In this paper, we propose a customized low power technique for high performance DRAM systems, namely the Page Hit Aware Write Buffer (PHA-WB). The PHA-WB improves DRAM page hit rate by buffering write operations that may incur page misses. This approach reduces DRAM system power consumption and temperature without any performance penalty. Our proposed Throughput-Aware PHA-WB (TAP) dynamically configures the write buffer for different applications and workloads, thus achieves the best trade off between DRAM power reduction and buffer power overhead. Our experiments show that a system with TAP could reduce the total DRAM power consumption by up to 18.36% (8.64% on average). The steady-state temperature can be reduced by as much as 5.10°C and by 1.93°C on average across eight representative workloads.