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BIOS from A to Z

17. Deactivate Outmoded Graphics Functions

The "Video RAM Cachable" and "Video BIOS Cachable" options boost graphics performance on older machines running DOS - but they do nothing for Windows. So why bother with them at all ?

Set both the "Video RAM Cachable" and "Video BIOS Cachable" options to "Disabled". While you’re at it, deactivate the "VGA Palette Snoop" as well, if this option appears. You can also safely deactivate the "System BIOS Cacheable" option (see Screenshot G) - it no longer provides a performance boost, and in some cases, may actually have a negative impact on system stability.

18. Install Texture Memory

The option for "Graphics Aperture Size" (which may show up as "AGP Aperture Size") was originally intended to help AGP graphics cards make more efficient use of system RAM when rendering graphics textures. This function has become outmoded now that many graphics cards have 128 MB or even 256 MB of video RAM onboard. At the same time, video RAM typically runs faster than system RAM. The old rule of thumb, often stated as "Set the graphics aperture size to half the RAM in your system," thus no longer applies. It’s better to set texture memory to an optimal size instead.

Set the value for the "Graphics Aperture Size" which may also show up as "AGP Aperture Size" to "128" or "64" MB instead.

19. Modify Clock Settings

This trick prevents problems with an AGP card when overclocking the Front Side Bus (FSB).

The menu item "AGPCLK/CPUCLK" (may show up as "AGP Clock") appears on systems with motherboards for which the manufacturer provides overclocking functions. If present, set its value to "Fix". This prevents overclocking the FSB from also automatically overclocking the AGP graphics card. A value of "1/1" causes the AGP card to run at the same clock rate as the FSB. A value of "2/3" sets the AGP clock to 2/3 of the FSB clock rate, so that 100 MHz for the FSB translates into 66 MHz for the AGP card.