Three-dimensional (3-D) integration technology provides various architectural opportunities including huge memory bandwidth. This paper proposes versatile stream buffer architecture to work as a secondary victim cache as well as the conventional stream buffer. The versatile stream buffer utilizes empty spaces to exploit massive memory bandwidth provided by 3-D integration technology and to reduce memory access frequency. Performance evaluation results show that the proposed mechanism with a 16KB stream buffer and a 4KB victim cache can achieve better performance than the conventional L2 cache with the capacity of 256KB and 2MB by 10% and 3%, respectively. The proposed mechanism reduces the miss rate by about 12% more than the conventional L2 cache with the capacity of 256KB.