Whether a laptop power adapter is universal depends on multiple factors. Firstly, laptops of different brands and models typically use different power adapters, and each brand and model has specific power requirements, including voltage, current, and plug shape. Therefore, in most cases, the power adapters of laptops of different brands or models are not interconnected.

Secondly, even if two laptops use the same plug shape, their voltage and current requirements may be different. If the voltage and current of a power adapter do not match the requirements of a laptop, it may cause the battery to fail to charge or the power supply to be insufficient, and may even damage the laptop.

However, there are also some special circumstances. Some brands and models of laptop power adapters may have compatibility labels that indicate which models of laptops the adapter is suitable for. In addition, some brands and models of laptops may use the same or similar power adapter specifications, making them interchangeable.

But overall, to ensure safety and effective charging, it is recommended to always use a power adapter that matches the laptop. If considering using other brands of power adapters, carefully compare their voltage, current, and plug shape parameters to ensure they match the requirements of the laptop. If unsure of compatibility, it is best to consult the manufacturer or professional maintenance personnel for advice.

In summary, laptop power adapters are not completely universal, but their interoperability needs to be determined based on specific brands and models.