XFX GeForce 9800 GX2 Hands-On Preview

By: James Yu Posted on March 18, 2008

[UPDATE 03/25/08: We have updated the story with Quad SLI performance results in Windows Vista SP1.]

We knew that Nvidia's flagship GeForce 8800 Ultra's days were numbered after the graphics manufacturer released the GeForce 8800 GT late last year. A single GeForce 8800 GT can't outperform an Ultra, but two GTs will, and the two cards can be had for less than the price of a single Ultra. AMD also added pressure on the Ultra with the release of its dual-GPU ATI Radeon HD 3870 X2. Nvidia has today responded with a new flagship card, the GeForce 9800 GX2.

The GeForce 9800 GX2 promises top performance thanks to its two onboard GeForce 9800 GPUs, featuring a combined total of 256 processing cores clocked at 1.5GHz. In comparison, the GeForce 8800 Ultra has only 128 processing cores at the same clock speed. The GX2 also comes with an equally large price tag, with an estimated retail price ranging from $599 to $649. Our XFX GeForce 9800 GX2 came with Company of Heroes and an "I'm gaming, Do not disturb" doorknob hanger.

Gallery

It's easiest to think of the GeForce 9800 GX2 as SLI on a single card. The card has two stacked printed circuit boards, one for each GPU, similar to the design of the GeForce 7950 GX2. However, unlike the 7950, the 9800 GX2 comes encased in a sleek plastic enclosure. The two GPUs won't double the frame rates over a single chip due to SLI overhead, but should show decent gains ranging between 1 and 2x depending on the application. The card has 1GB of memory with 512MB dedicated to each chip. The GX2 supports PCI Expresss 2.0 and DirectX 10. ATI's latest cards support DirectX 10.1, but we haven't seen any games that take advantage of it yet.

Nvidia has confirmed that you will be able to run two GeForce 9800 GX2 cards together for Quad SLI, but the company isn't letting any publications post quad-GPU numbers until next week, when its PC system partners make their Quad SLI announcements.

GPU	GeForce 9800 GX2	GeForce 8800 Ultra	GeForce 8800 GTX	GeForce 8800 GT
Price	$599-649	$649	$399	$189
Stream Processors	256	128	128	112
Shader Clock	1.5GHz	1.5GHz	1.35GHz	1.5GHz
Core Clock	600MHz	612MHz	575MHz	600MHz
Memory	512MBx2	768MB	768MB	512MB
Memory Clock	1GHz	1.08GHz	900MHz	900MHz
Memory Interface	256-bit	384-bit	384-bit	256-bit

Our XFX GeForce 9800 GX2 has HDMI and two dual-link DVI-I connectors. The dual-link DVI connectors can handle high-resolution monitors, and can also run VGA monitors using analog adaptors. HDMI output connectors have become more important now that video cards are capable of accelerating HD video playback. The GX2 has a SPDIF audio input connector on the top of the card to supply the audio feed from the motherboard or an external graphics card for HDMI output.

A performance monster like the GeForce 9800 GX2 also comes with hefty power requirements. Nvidia recommends using a 580W power supply with a single card and 850W for two GX2s running in SLI. XFX recommends 630W or more for a single GX2 and 680W or more for an SLI configuration. You also need to make sure that the power supply has the necessary six- and eight-pin power connectors for the card. The power input connectors can be a little snug--we had to snap off some of the plastic between the two connectors in order to get our Targas power supply plugs to fit into the card.

Power-conscious users might be interested in the GeForce 9800 GX2's new HybridPower feature that lets you switch between integrated graphics and the GX2 depending on the graphics workload. The switch allows users to save power while running normal desktop applications that don't need the video card's processing power. The feature currently only works with HybridPower-enabled motherboards with integrated GeForce graphics.

Judging by the specifications, we expected the XFX GeForce 9800 GX2 to perform similarly to a GeForce 8800 GTX or Ultra SLI system. We currently don't have any GeForce 8800 Ultra cards, but our dual GeForce 8800 GTX configuration, currently selling for close to $800, should be a formidable challenge. We also tossed in an ATI Radeon HD 3870 to see how another dual-GPU card compares, and a GeForce 8800 GT SLI setup to see how one of Nvidia's best SLI offerings stacks up to the newest 9800. We had to fall back to Windows XP SP2 in Crysis and Unreal Tournament 3 due to irregular driver performance in Vista.

Windows Vista System Setup: Intel Core 2 Extreme QX9775, Intel D5400XS, 4GB FB-DIMM (2x2GB), 750GB Seagate 7200.10 SATA Hard Disk Drive, Windows Vista 32-bit. Graphics Cards: GeForce 9800 GX2 1GB ,GeForce 8800 GTX 768MB, GeForce 8800 GT 512MB, Radeon HD 3870 X2 1GB. Graphics Drivers: ATI Catalyst 8.3, Nvidia ForceWare beta 169.44, Nvidia ForceWare beta 174.53.

Windows XP System Setup: Intel Core 2 Extreme QX9650, eVGA 780i SLI, 2GB Corsair (2x1GB), 750GB Seagate 7200.10 SATA Hard Disk Drive, Windows XP SP2. Graphics Cards: GeForce 9800 GX2 1GB ,GeForce 8800 GTX 768MB, GeForce 8800 GT 512MB, Radeon HD 3870 X2 1GB. Graphics Drivers: ATI Catalyst 8.3, Nvidia ForceWare beta 169.44, Nvidia ForceWare beta 174.53.

The GX2's performance level certainly justifies its place atop the GeForce 9 series product line. The GeForce 9800 GX2 more than doubled the performance of the GTX in Unreal Tournament 3 and offered a more than 50 percent improvement in Crysis and Call of Duty 4. The GX2 also beat out the $800 GTX SLI setup in Unreal Tournament 3, and matched the SLI system in Crysis before falling slightly behind in Call of Duty 4.

We ran a whole new set of benchmarks with two XFX GeForce 9800 GX2 cards running in Quad SLI on Windows Vista SP1. Some of the performance numbers are very different from the results of prior tests due to the Windows Vista SP1 update. We also had to switch from Windows XP to Windows Vista because Quad SLI currently works only in Windows Vista.

Windows Vista System Setup: Intel Core 2 Extreme QX9775, Intel D5400XS, 4GB FB-DIMM (2x2GB), 750GB Seagate 7200.10 SATA Hard Disk Drive, Windows Vista 32-bit SP1. Graphics Cards: GeForce 9800 GX2 1GB ,GeForce 8800 GTX 768MB, Radeon HD 3870 X2 1GB. Graphics Drivers: ATI Catalyst 8.3, Nvidia ForceWare beta 169.44, Nvidia ForceWare beta 174.53.

At an estimated cost of $599-649, the XFX GeForce 9800 GX2 isn't for everyone. If you absolutely have to have the best performance at any cost, then you'll want to pick up one or two GX2s for your gaming rig. More cost-conscious buyers should look at lower price points where you can get more bang for the buck. Keep in mind that while expensive, top-of-the-line cards aren't for average PC gamers with average salaries, the graphics companies understand that these flagship cards create a halo effect over the rest of the product line. The high prices can also serve as anchor points for comparison shopping. Buyers who can't afford a GeForce 9800 GX2 might view the more affordable GeForce 9600 GT or GeForce 8800 GT cards as bargains in comparison.