Model Specific Register Many CPU manufacturers include undocumented registers on their processors. Because these registers are model specific, they can be used to help identify the model of the processor installed on a given machine. The Intel instructions to read and write to MSRs are RDMSR and WRMSR respectively. These instructions allow access to the MSR specified in the ECX register. ... Undocumented Pentium MSRs: http://x86.ddj.com/articles/p5msr/pentiummsrs.htm Entry created: Tue Mar 18 20:48:32 EST 2003 Entry owner: Michael Still (mikal@stillhq.com) Status: Unfinalized