Onboard or External Graphics?

Integrated or onboard graphics is something a gaming freak wouldn't like to touch with a barge pole. That's because the latest games such as Doom 3 and Half Life 2 have set the hardware requirements far beyond what onboard graphics can handle. Moreover, even the software libraries required to run these games, viz DirectX and OpenGL, have introduced many features that are not supported by onboard graphics. So, for a gamer, buying a separate 3D-graphics card is a pre-requisite to get support for these features for better gaming. This demarcation between onboard graphics and separate graphics cards brings an interesting situation. What happens if these features also get integrated with onboard graphics? Would that mean the end of graphics boards? Let's take a look at what technological developments are taking place in each. 

The concept of onboard graphics really came up when Intel integrated graphics with its 810-chipset based motherboards for the PIII processor. Intel didn't leave an option for putting in an additional graphics card, forcing people to use only onboard graphics. Onboard graphics were capable of handling most day-to-day work, which eliminated a lot of graphics cards from the market. Intel later came up with the provision to add graphics cards as well, and this changed the face of the graphics market. People didn't feel the need to buy a separate graphics card, because the onboard card served the purpose well. Intel brought iterations of its onboard graphics, with the latest one being the Extreme Graphics 2 core for the P4 processor. Along the way, two major graphics manufacturers joined the race by introducing their motherboard chipsets with onboard graphics. These were NVIDIA with its Nforce and Nforce 2 chipsets, and ATI with its latest Radeon 9100 IGP (Integrated Graphics Port). So today, with graphics manufacturers in the race, onboard graphics have become quite powerful. You can play games, watch movies, or run high-end graphics applications. That brings us to the million-dollar question of why go for a separate graphics card. 

If we look at the basic desktop, the first level of difference would be in the support for graphics libraries. The onboard graphics don't support all the features offered by DirectX, and even if they did, they wouldn't support the latest version. Currently, the latest version of DirectX is 9. Moreover, onboard graphics usually share 8 to 64 MB of system memory or RAM, while graphics cards use their dedicated memory for better performance, which could range from 64 to 256 MB.

Results of a graphics card with (right) and without (left) DirectX 9 support

This dedicated memory is connected to the system using a dedicated bus (either AGP or the latest PCI Express bus). This bus also has a positive effect on graphics performance, as the graphics processor does not have to share it with any other device. So performance wise, it is difficult for integrated graphics to match up to that of the external cards. The other advantages that external graphics cards enjoy over onboard ones are extra DVI and TV outputs. Many cards also have the capability of displaying output on two monitors simultaneously. Now with the advent of PCI Express the number of monitors supported can even go up to four. The latest X200 motherboard from ATI, for instance, can support up to three monitors using its one onboard IGP (Integrated Graphics Port) and two more by adding a PCI Express graphics card. So the advent of onboard graphics is not the end of external graphics cards. In fact, this has boosted the graphics cards business to produce better and feature-rich graphics cards. There's a race to produce graphics cards that can bring in more realism into the graphics quality that they produce.

There's a race in the software market, especially DirectX and OpenGL, to bring out libraries that can consume all the power of the latest graphics cards. And

there's a race in the gaming and applications market to have more realistic games and applications. The sad part is that most graphics manufacturers are keeping the gaming market as their primary focus, even though their cards are capable of doing much more. 3D animation, cinema and GIS are just a few areas where any amount of graphics power is insufficient. 

Ankit Kawatra