What else is going on? First, some rumors and speculations:ġ) The Bus fight: 2D chip and Rush are competing with each other for PCI.Ģ) The Chip fight: Various rumors of incompatibilities were floating around, I trust none of them. This does not yet fully explain much since the Rush performance deficiency is rather big. The setup works 16 clocks on perspective corrected triangle or 7 without the correction. This helps with weak processors, however the setup engine is not fast enough to keep up with stronger CPUs (like Pentium II), resulting in smaller scaling than Voodoo Graphics. 3dfx implemented full triangle setup in Rush, making it offload more of CPU work. Basic specification was identical to original Voodoo Graphics with exception of early boards clocked at 45 MHz, 10% less. The Rush was basically reworked Voodoo chipset developed during 1996 and therefore codenamed SST-96. Alliance chips have 175 MHz ramdac and Micronix only 160 MHz. 3D resolutions of Rush are limited by frame buffer size and 2D chip refreshing capabilities. Setting frequency one or two MHz lower solves it. The AT25 is clocked at 72 MHz and memory cannot keep up with it, creating artifacts on the desktop (!). 3dfx parts are running at 50 MHz, this card is well suited for comparison with classic Voodoo Graphics. TMU has usual 2 MB of memory and frame buffer is 4 MB, but shared between 2d and 3d engines. Note how the FJR chip is now smaller than pixel engine of Voodoo Graphics and it lost 32 pins as well. My board in the test is A-Trend Helios 3D with AT25 2D core and memory from Alliance. The Micronix chip did not help the Rush either, in fact it was worse than Alliance. Of course, all 3D ended up on the 3dfx chipset, but performance was unexpectedly lacking behind Voodoo Graphics. That does not put much faith in Rush performance and horribly underestimates suckiness of AT3D. What happened? Bad sign were rumors of Direct3D being handled by AT3D and Voodoo chipset being used for Glide games. In the beginning of 1997 first board by Hercules came out, but the response was far from positive. AT3D single chip accelerator was going to be combined with the Voodoo Rush chipset in a single card. The world was just realizing how strong Voodoo is when 3Dfx and Alliance together announced a complete graphics solution. But their 2d chip was far from complete and 3Dfx searched for other options. First partnership was formed with Orchid's Micronix already in the spring of 1996. And since 3dfx did not have yet enough resources to develop 2D internally they had to team up with other companies. If there was any weakness of Voodoo Graphics it was it's 3D-only implementation.
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