PC Hacks

Chapter 7. Video Hacks

Introduction: Hacks #68-74

Except for the CPU and memory, the video card handles more data more often than any other component in your PC. It's possible for a 1024768 display with a color depth of 32 bits (4 bytes) refreshed 60 times per second to move tens of megabytes per second—if the entire screen refreshed with new data at each screen refresh interval. This is a lot of data, and it does not include the processing and rendering the video card's CPU has to handle to generate a constantly dynamic display. Enhancing video performance is most important to graphic designers and gamers, but it can also make Windows less sluggish and clunky for the rest of us.

Overall video performance is affected not only by the speed, quality, and features of the video adapter card (which in some cases you may overclock just as you can your CPU and system RAM) but also by which I/O interface your video adapter uses—ISA, PCI, or AGP (including video adapters built onto the system board).

The ISA and PCI buses can be used for just about every type of I/O device there is, from modems to network to video adapters. A lot of activity is going on within these buses. The 16-bit (2-byte wide) ISA bus runs at 16 MHz, yielding a maximum throughput of 32 megabytes per second (MBps). The 32-bit (4-byte wide) PCI bus runs at 33 MHz, yielding maximum throughput of 133 MBps.

The AGP bus is dedicated specifically to graphics—a straight pipe from the PC's CPU to the display—and it's ...