First of all, it is important to know what is the brightness level of 3m Led Light Strip, which is measured in lumens. The brighter the light, the more lumens, and the more lumens, the brighter the light. Different types of light bulbs have different lumens, and this will affect your brightness level. The more lumens, the faster the light bulb will burn out. One of the most common issues with LED strip lighting is dimness. The light output of an LED strip is directly proportional to the voltage applied to it. If an LED strip is dim, it might mean that the voltage regulator onboard is not working properly. In such a case, you need to replace the regulator on board. LED strip lights work on DC voltage which is regulated. The amount of power that the strip consumes varies with the brightness of the strip. If the voltage is not regulated, the strip will consume a lot of power. But you need to make sure that the power supply is capable of handling the load or the strip will get damaged. Also, you need to ensure that the strip is wired properly and all the resistors, diodes, and capacitors are soldered properly.