The GeForce 9800 GTX uses a dual-slot design that requires two 6-pin PCIe power connectors for proper usage. If power is not properly hooked up to the GeForce 9800 GTX the video card will sound an alarm and you will definitely hear it. When it comes to power supplies a single GeForce 9800 GTX, needs at least a 450-watt power supply unit for proper operation. For each additional GeForce 9800 GTX added to the system, 156 watts more power is recommended as that is the maximum board power that each card can consume. This means those that want to run triple SLI with three of these cards will need at least a 762W power supply according to NVIDIA. If you plan on running triple SLI make sure you have six 6-pin PCIe connectors available as many older power supplies will need adapters as they didn’t come with this many power headers. NVIDIA also did something we have never seen a video card company do, with this launch. They suggested that with a single GeForce 9800 GTX one should use at least an Intel Core 2 Duo E4500 CPU and for SLI and 3-way SLI a Core 2 Duo E8500 CPU. While this is not shocking it is interesting to see CPU suggestions for video cards.
On the rear of the GeForce 9800 GTX one will one will find the usual dual dual-link, HDCP-enabled DVI-I outputs for connection to analog and digital PC monitors and HDTVs, a 7-pin analog video-out port that supports S-Video directly, plus composite and component (YPrPb) outputs via an optional dongle.
The GeForce 9800 GTX also provides native support for HDMI output, using a certified DVI-to-HDMI adaptor in conjunction with the built-in SPDIF audio connector. This solution differs from ATI by the fact is requires an audio connection from the motherboard or sound card to the video card. Both ATI and NVIDIA solutions have the outgoing audio going through the HDMI cable to the TV or receiver, but only NVIDIA needs internal connections to make this happen.
Once the audio connection is taken care, all one needs to do is attach the DVI-to-HDMI adaptor to one of two dual-link, HDCP-enabled DVI-I outputs. After the SPDIF audio connection has been made and the adapter is used with an HDMI cable you’ll be able to output video on an HDTV.