The present document defines the current standpoint of ISG OEU members in relation to the operational measurement of energy performance and selection of ICT physical servers. It defines an energy performance operational KPI and its related measurement points@ measurement protocols and transmission. The measured KPI is simply and unequivocally linked to the measured ICT physical server. It defines technical KPIs allowing to predict energy consumption and task efficiency for specific uses. The technical KPIs is simply and unequivocally linked to the measured ICT physical server. These KPIs allow differentiating energy consumption by noble parts (e.g. CPU@ memory@ disk@ I/O) of ICT physical server of the overall consumption including cooling and power supplies. An ICT physical server is a general-purpose ICT equipment with its own dedicated power supplies. The aforementioned KPIs applies to specified configurations@ including type and count of CPU@ memory@ storage@ power supplies@ cooling (e.g. fans) and any other add-on hardware expected to be present in production. In particular@ for a blade chassis@ it includes the blade enclosure@ the blades and all the required I/O interfaces (e.g. switches) included in the blade enclosure.