Board analysis

At the heart of ATI’s Radeon X1900 GT lies the exact same R580 GPU that currently powers ATI’s Radeon X1900 XT/XTX cards. Unlike the Radeon X1900 XT and X1900 XTX however, the X1900 GT doesn’t boast 48 pixel shaders, instead ATI disables 12 pixel shaders for a total of 36. Four texture units and render back-ends (ROPS) are also disabled in the X1900 GT, reducing the total number of texture address units and ROPS to 12 (from 16 in the Radeon X1900 XT/XTX).

Fortunately, the vertex shaders carry over unchanged from the more senior X1900 cards, as the Radeon X1900 GT sports 8 vertex shading units; ATI also makes no changes to the X1900 GT’s memory controller, as it’s outfitted with the same programmable 256-bit memory interface with eight 32-bit memory controllers that was first introduced in the Radeon X1800 XT late last year. Clock speeds are down from the Radeon X1900 XT and XTX though as the X1900 GT’s graphics core is clocked at 575MHz, that’s 50MHz lower than the Radeon X1900 XT and 75MHz shy of the X1900 XTX’s 650MHz core clock speed, while the X1900 GT’s memory is clocked at 600MHz (1.2GHz effective). In comparison, the X1900 XT’s memory runs at 725MHz.

Top of the Sapphire X1900 GT

Back of the card

The Sapphire X1900 GT card

At first glance, Sapphire’s Radeon X1900 GT card looks like a clone of ATI’s Radeon X1800 XL, the X1900 GT uses the same board design and similar cooling, but actually one key change has been made that makes the board easier to live with on a day-to-day basis: it generates less noise than the Radeon X1800 XL did.

See how similar the X1800 XL and X1900 are?

Additional power on the X1900 GT

You can see Ruby underneath the Sapphire sticker

ATI uses the same heatsink/fan unit as the Radeon X1800 XL – if you peel the Sapphire X1900 GT sticker off you can literally see Ruby underneath – only the card’s fan has been tweaked to run at lower RPMs overall. The card’s fan still runs at roughly 2500 RPMs in 2D mode, just like the Radeon X1800 XL, but ATI has raised the temperature thresholds at which the fan spins up, and even when it does spin up, the RPMs aren’t as high: whereas the fan on X1800 XL could crank up to full tilt after even light gaming sessions, we never saw the fan on the X1900 GT crank up to full speed, even when overclocking and/or during extended usage in games. It was only when we manually adjusted the RPMs that we were reminded of the Radeon X1800 XL; if we didn’t have both cards in-house for testing our ears would’ve sworn we were using two different coolers, it really is a remarkable difference between both cards.

The only other difference between the X1800 XL’s board design and the X1900 GT is the additional power circuitry used on the X1900 GT card. Everywhere else the two cards are the same. Sapphire’s X1900 GT is equipped with two dual-link DVI connectors, just like the Radeon X1800 XL, as well as ATI’s Rage Theater chip, providing video-in/video-out functionality (VIVO).

Sapphire also continues to provide their Sapphire Select software bundle with their Radeon X1900 GT card. With Sapphire Select, you have the option to choose from one of four games: Tony Hawk’s Undergound 2, Prince of Persia: Warrior Within, Brothers in Arms: Road to Hill 30, and Richard Burns Rally. You can try all four games for up to one hour, at that point you’ll then pick one game to be unlocked for the full version. The other three games can then be purchased at a discount if you’d like (on higher-end X1900 cards Sapphire allows you to unlock two games).

In addition to the Sapphire Select DVD, Sapphire also includes a copy of CyberLink PowerDVD 6 2-channel edition, and PowerDirector 4DE. Hardware accessories included with the card are a 6-pin PCI-E power connector, two DVI adapters, S-Video and composite video cables, a component video cable, and VIVO cable.