3D Fuzion was a downmarket subsidiary of now-defunct BFG Technologies. Like BFG, they were one of many NVIDIA OEM partners. They sold entry, midrange and high-end video cards utilizing NVIDIA chipsets, just like BFG Technologies. The primary difference between 3D Fuzion and BFG-branded boards was that the 3D Fuzion boards didn't offer a Lifetime Warranty or 24/7 technical support. In addition, they didn't deviate from NVIDIA's reference design clock rates for their video cards, while BFG was one of the first NVIDIA OEM vendors to sell overclocked video cards directly to the consumer.
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3D Fuzion Wikipedia(Text) CC BY-SA