A computer includes various features that improve its functionality and/or ease of use. A modular electronics cartridge that includes a piston seal and opposed-direction latches removably engages a cartridge bay of the computer. A high intensity touch-screen display and a high power processor are disposed in a sealed compartment of the computer, and a remote heat exchanger is used to cool the sealed compartment. An interface converter/adapter converts a standard mini-PCI Express slot into a specialized mini-PCI Express slot with voice capabilities. SIM and microSD card slots mount to a pivoting door on the computer such that opening the door provides easier access to the card slots.