An Empirical Study of Memory Hardware Errors in A Server Farm Xin Li, Michael C. Huang, and Kai Shen Lingkun Chu University of Rochester Ask.com The integrity of system hardware is an important requirement for providing dependable services. Understanding the hardware's failure mechanisms and the error rate is therefore an important step towards devising an effective overall protection mechanism to prevent service failure. In this paper we discuss an on-going case study of memory hardware failures of production systems in a server-farm environment. We present some preliminary results collected from 212 machines. Our observations under a normal, non-accelerated condition validate the existence of all failure modes modeled in the previous literature: single-cell, row, column, and whole-chip failures. We also provide a quantitative analysis of the error rates.