April 1999 Super7 3D Video Accelerator Comparisonby Anand Lal Shimpi on April 10, 1999 1:15 AM EST
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Setting It Up
Installing an AGP accelerator on a Super7 motherboard is a bit more complicated than doing so on a Socket-370 or a Slot-1 motherboard based on an Intel chipset. This is simply because you have to take into account the configuration and setup of the drivers that enable a feature of the AGP specification known as the Graphics Address Remapping Table, or GART for short. The importance of GART support to a true AGP accelerator is this, if you happen to have an incredibly large texture that cannot fit within your graphics cards local memory, the AGP bus can allow for it to be transferred quickly for storage and later retrieval to and from system memory. But the AGP bus can only transfer the textures, how is it stored? The Graphics Address Remapping Table essentially allows the video card to address texture maps as single data objects, a process critical to getting the full benefit from AGP texturing (the storage/retrieval of large textures to and from system memory), one of the major benefits of the Accelerated Graphics Port.
Unfortunately for Super7 users, GART support is natively provided and optimized by Windows 98 (and Windows 95 OSR2) for Intel AGPSets, or Intel chipsets with AGP support, such as the i440LX, i440BX, and the i440GX. Although Windows 98 does offer support for VIA and ALi based AGP solutions, the optimizations are not nearly as thorough as those provided for their Intel counterparts, for the same reasons discussed in the opening of the article. The responsibility then fell upon VIA and ALi to produce updated virtual device drivers that would provide full GART support among other features to users of motherboards based upon their chipsets under Windows 98, and this they did.
The most common cause of Super7 AGP video card incompatibilities appears to be the drivers, not the chipset itself, where a lack of proper support for the specification as defined by Intel (since they are the dominant force in the industry, all graphics chipset manufacturers pursue 100% compatibility with their chipsets first) often results in stability problems and compatibility problems. Likewise, the most commonly overlooked step in setting up a high performing yet stable Super7 system with an AGP graphics accelerator is the simple act of loading the AGP drivers from the chipset manufacturer.
A second problem AnandTech ran into when experimenting with the latest 3D accelerators and two of the most popular Super7 chipsets (the Aladdin V and MVP3) was the ambiguous setting referred to as AGP Turbo Mode. This feature, which is common to both Aladdin V and MVP3 based motherboards, illustrated a direct correlation to the performance of the AGP graphics card installed. Enabling AGP Turbo Mode (accomplished through the BIOS on Aladdin V based boards and through the VIA AGP setup utility on MVP3 based boards), as you can easily assume, increases the performance of your system, however it also happens to be one of the most commonly overlooked steps in setting up a Super7 system. Most Aladdin V motherboard owners may not be aware of the setting which should be present in the latest revisions of their BIOS setup files, however it seems as if VIA wisely chose to include the option to enable/disable the Turbo mode in their AGP setup utility. This is not the same AGP Turbo Mode that BX motherboard owners may be familiar with, as it does not simply run your AGP bus at the FSB frequency. The setting seems to enable the full set of AGP functions as defined by the specification, seemingly directly related to the GART as AGP video cards with a poor implementation of the specification generally exhibit erratic behavior after having this option enabled as will soon be explained from AnandTechs findings.
If you take the above precautions into account while setting up a Super7 system with an AGP video accelerator, youll end up with the highest chance of achieving a successful install, a rate which has increased tremendously due to the presence of more mature AGP drivers from the two major Super7 chipset manufacturers.
For purposes of benchmark integrity, each video card compared received a completely formatted test hard drive without any foreign video drivers present and the latest revision of the video manufacturers drivers as well as the motherboard chipset manufacturers drivers were installed, current as of April 9, 1999.