Laptop computers, once relegated to the status of glorified electric typewriters, have nevertheless continued to develop as briskly as their desktop counterparts in terms of computing power, storage, and general usability. By 2010, higher end laptops were capable of acting as true personal computer (PC) replacements in all but the most demanding situations. One of the biggest design advances that has made this possible is the offloading of graphics rendering from the laptop's main central processing unit (CPU) to a separate, purpose-built mobile video card designed to fit within the form factor of a laptop body.
The mobile video card is a relatively new addition to the parts list of laptop makers. A variety of technological limitations, not the least of which being the small size and low resolution of laptop screens, precluded the idea that a laptop could be used for taxing graphics-rendering work or gaming for many years. As screen technology evolved, however, demand increased for laptops that could perform more of the same duties as full-sized desktops.
Though usable for almost all modern gaming and graphics-rendering applications, a given mobile video card remains inferior in all aspects to a desktop counterpart of the same price. This is due to three main limitations: size, heat, and power consumption. Given the inescapable limitations due to size, there is only so much that can be packed into a mobile version of a graphics card, meaning they will always lag behind desktop cards in terms of raw processing power.
The second main drawback mobile video cards suffer from is extreme power consumption. A laptop user playing a computer game on battery power will see the life of the battery cut in half, or more. This severely restricts the advantage of laptops as a mobile device, and is one of main criticisms of laptops as gaming machines. Critics argue that if a laptop must be plugged in to play a game, perhaps users should just get a desktop and enjoy all other advantages they offer.
In use, a mobile video card generates a lot of extra heat. This is a particular problem in the limited space of a laptop. Heat dispersion is one of the biggest design challenges that face laptop manufacturers, who must balance more powerful and hotter-running parts with the ever-present fact that every advance means more heat to dissipate in the same amount of space. Laptop burns are an increasingly common phenomenon, as temperatures on the bottom of a laptop can reach well past 160°F (71°C). It is no small irony that a laptop doing heavy graphics processing should be kept on a table or desk, and not on one's lap.
Another general limitation of mobile video cards is the fact that they are very hard to replace. Desktop graphics cards literally slot in and out of the motherboard, making them an easy part to upgrade. Mobile versions are much less modular, and without going to great effort or cost, cannot be upgraded. Given the ever-advancing computing industry, this is a particular drawback for graphics professionals who want to remain on the cutting edge.
Despite these drawbacks, mobile gaming and graphics work remains a growing part of the computer industry. Mobile video card technology likewise continues to improve, as manufacturers work to solve the unique design challenges posed by laptops. Though they will likely always trail desktops in brute strength, demand for portable workstations continues to increase as users choose to compromise power for portability.