A method for analyzing load run test results of a computer system includes providing a plurality of performance measure sets derived from a first series of load run tests performed over a same time period. By simplifying the user managed power states to On and Standby, the computing device preserves its execution context by default when the machine is powered down. Also, the thickness of a set of the tabs may be equal to the thickness of the leg to which they are welded. A clock shift in the other IO subsystem with respect to the one IO subsystem is calculated from the calculated ideal reception time and the recorded reception time. The backrest structure includes a backrest-adjusting device to provide the linkage movement and also offer multiple stage adjustment of the backrest angle.