In general, in one aspect, the disclosure describes a laptop computer that can allow for enhanced cooling of a passively cooled notebook while maintaining the desired waterproof and dust resistance of the design. This is achieved by creating a separate cooling channel where air can flow through to provide cooling to an electronics enclosure connected thereto. The cooling channel may utilize membranes (e.g., hydrophobic membranes) to protect again water and dust penetration. In some cases, two fans are used in opposite directions in order to automatically clean the membranes from dust accumulation.