Nvidia Riva TNT, 26 pin header at top of card? \ VOGONS

Nvidia Riva TNT, 26 pin header at top of card?

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First post, by rwGast

Posted on 2026-06-30, 02:32

rwGast Offline

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Im got a 2 old dell xps r450s, ive been using them to build one good computer. They both have Diamond TNT gpus in them. The cards have a 26pin header at the top, searching i noticed ALL tnt cards have this 26pin header. I have searched but cant find anything about it! Is it nvlink? Maybe a path for ram expansion? Cant be just a debug header seeing as it is on every tnt card!

Reply 1 of 2, by NeoG_

Posted on 2026-06-30, 03:11

NeoG_ Offline

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The 26 pin header on cards from that time is the feature connector. It allowed image data to be passed to the card EG from a dvd decoder or capture card without an external loopback cable.

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Reply 2 of 2, by MagefromAntares

Posted on 2026-06-30, 04:48

MagefromAntares Offline

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Hi,

As @NeoG_ posted this is the VGA feature connector.

If you are interested in more details this is the pinout for the VGA feature connector(AFAIK while used on a great deal of cards, the standard for it was not really enforced, and as such the NC pins depending on the card might actually lead somewhere):
https://www.repairfaq.org/REPAIR/F_Pinouts1.html#PINOUTS_009
Also an edge connector can be used instead of a pin header connector, for example the card on this page:
https://www.dosdays.co.uk/topics/Manufacturer … rofessional.php

There was an 80-pin version of the connector called the VESA Advanced Feature Connector, but that is more rare than the VGA feature connector:
https://theretroweb.com/misc/documentation/va … 62375337361.pdf

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