The efficiency of the driver or power supply will have an impact on the Lm/W and this can be showed in an easy but important way by the following. We will use a 1000 lumen lamp with a 10w output as an indication and then apply a driver option as below with a combined 100Lm/W

A driver that is 90% efficient = 11w giving 90Lm/W

A driver that is 70% efficient =14.3w giving 70Lm/W