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                                                                    EXHIBIT 23.8
 
                          CONSENT OF JAMES L. HOPKINS
 
     The undersigned hereby consents to be named in this Registration Statement
on Form S-4 as a person designated to become a director of 3Dfx Interactive,
Inc. ("3Dfx") upon the consummation of the merger of STB Systems, Inc. and 3Dfx.
 
Signature: /s/     James L. Hopkins
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Date: April 15, 1999
