A discharge lamp and a method for forming the lamp, the lamp including a ceramic discharge vessel defining at least part of a cavity containing a metal halide (MH) chemical filling having a power factor of between about 0.75 and 0.85 located within the cavity; and one or more feedthroughs having first and second ends, the first end located in the cavity. The cavity may have an internal length LINT and an internal diameter DINT that are proportional to each other, such that an aspect ratio defined as LINT/DINT is less than or equal to two. The lamp may be started and operated with a probe-start ballast without an internal igniter circuit or without a starting electrode (or internal igniter).