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A Closer Look at the 9800 GX2

The GeForce 9800 GX2 card is a real departure from previous NVIDIA designs.  In some respects, the GeForce 9800 GX2 is like the 7950 GX2 in that they both utilize a pair of PCBs linked together on a single graphics adapter.  The GeForce 9800 GX2, however, has a more innovative design in our opinion.  We think you'll agree after you see the goods...


With the GeForce 9800 GX2, each GPU (and its frame buffer memory) resides on its own PCB.  And sandwiched in between the PCBs is a single, large heatsink and fan that cools the GPUs and RAM.  The rear of the PCBs features a cut-out that allows air to be pulled in from either side, where it is funneled through the center of the card and ultimately exhausted from the system.  The entire assembly is encased in a metal shell that not only protects the components inside, but also helps dissipate heat.

The GeForce 9800 GX2 features a pair of dual-link DVI-I outputs in addition to an HDMI output, that also carries audio signals.  To one side of the GX2's 6-pin PCI Express power connectors, there is a tiny S/PDIF input header.  GeForce 9800 GX2 cards will include a cable that connects a motherboard's S/PDIF output to this header, where it is then channeled to the HDMI output.  And while the GX2 has a dual DVI outputs, multi-display functionality still operates like two cards - multi-GPU performance SLI mode must be disabled for a multi-monitor setup.  We should note, however, NVIDIA plans to change this with a future driver release.


If you look close, also visible on the front of the GeForce 9800 GX2, up towards the top of the retention bracket, at a pair of LEDs.  One of the LEDs will be used to indicate the primary card in a Quad-SLI configuration, while the other indicated whether or not power is properly being supplied to the card.  The GeForce 9800 GX2 requires both a 6-pin and an 8-pin PCI Express power connector to be plugged in to operate.  Because the card can consume almost 200W (197W to be exact) NVIDIA requires both types of connector - using dual 6-pin connectors will not work.  An 8-pin connector must be plugged into the card for it to operate.


Up at the top of the card you can see its SLI edge connector.  As you probably expect at this point, two of these cards can be paired up for a Quad-SLI configuration.  We'll be talking more about that in a future article, so stay tuned.

With the GeForce 9800 GX2's external shell removed, you can get a better view of the card's innards.  Along the bottom, a ribbon cable connection the two PCBs together is visible, as are the vents in the PCBs and the large cooler.  We're sure some debate will ensure as to whose dual-GPU design is more elegant, NVIDIA's or ATI's, but what does that mean really?  It's the all around performance that counts.



We've also already begin receiving full-retail GeForce 9800 GX2 cards.  What you see pictured here is the ASUS EN9800GX2.  ASUS' take on the GeForce 9800 GX2 is much like the reference design, save for the custom decal affixed to the card's enclosure.  And as usual, ASUS includes a robust accessory bundle complete with a full version of the DX10 game Company of Heroes: Opposing Fronts.  We'll be bringing you a more detailed look at this card in the not too distant future.

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