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Sapphire Radeon HD 2900 XT CrossFire

Two retail Sapphire Radeon HD 2900 XT video cards, one Intel Bad Axe 2, and two CrossFire bridge connectors equals ATI’s most powerful graphics combination at this time for gaming. We find out if two Radeon HD 2900 XT video cards in CrossFire is worthy or a waste.

Introduction

To get all the juicy details on what makes the ATI Radeon HD 2000 family tick please read our ATI Radeon HD 2900 XT evaluation.

This is our first evaluation of a retail Radeon HD 2900 XT based video card, today we are evaluating Sapphire’s latest entry to the market. Sapphire is well known for being ATI loyal, and seeing as how they are ATI’s primary manufacturing and distribution partner, it makes sense. The Sapphire Radeon HD 2900 XT is your standard, to the bone, reference design. The same features you will find in our initial evaluation of the Radeon HD 2900 XT from ATI are the same here.

There are 700 million transistors inside based on a unique 80nm HS manufacturing process. There are 320 stream processing units and an external 512-bit memory interface with 512MB of GDDR3. You will find support for DX10, 8X multisample antialiasing and 16X angle independent anisotropic filtering. The clock speeds are exactly the same at 743 MHz for the core and 825 MHz (1.65 GHz DDR) for the memory. There is also the standard built in HDMI audio controller on board for outputting a full HDMI signal.

In our initial evaluation we looked at single video card performance compared to the competition, first with a 640 MB GeForce 8800 GTS then we followed up and showed you comparisons with a 320 MB GeForce 8800 GTS. In this evaluation we are going to cover single video performance again, but with even newer drivers and we will compare it to a multi-GPU configuration in CrossFire as well as NVIDIA’s SLI.

CrossFire

The Radeon HD 2900 XT supports what ATI calls native CrossFire. In native CrossFire ATI has built the compositing engine required for CrossFire into the ASIC itself. This means that every Radeon HD 2900 XT is capable of combing with another to make a CrossFire connection. There is no need for a master/slave scheme. ATI has also done away with the external dongle and has incorporated two internal bridge connectors atop each video card.

You do need two CrossFire connectors to make CrossFire work; it will not function with one. Each CrossFire connector will actually be shipped in each retail package itself instead of the motherboards. So if you get one retail video card you will have one CrossFire connector. When you purchase the second retail package you will get the other connector so you can CrossFire them.

One downside to the CrossFire connector we have encountered is the length of the connector itself. It seems that ATI will not provide a longer connector for those that wish to separate their video cards on their motherboards with three PCIe slots. With the short CrossFire connector you have to place both video cards in adjacent slots which means they rest right next to each other, smothering the video card in the primary PCI-Express slot of oxygen. It can really lead to a bad situation if you have an enclosed case and poor cooling. We run in an open-air environment, and even we put an extra 90mm on top of the video card combination to provide better cooling to the primary video card. See the pictures at the bottom of this page.

Sapphire Radeon HD 2900 XT

The Sapphire HD 2900 XT is packaged in a fair sized blue shiny box with window. We like windowed boxes, it gives you the chance to see exactly what is in the box so you know what to expect before opening it. Plastered on the front are a listing of key features such as 512MB of GDDR3, HDMI, HD Audio, VIVO, the inclusion of 3DMark and the Valve Black Box coupon.

On the side of the box you will find the hardware requirements and power supply recommendation. It is listed that a 550W PSU for single card, and 750W PSU for CrossFire is required, higher recommended. For CrossFire we suggest you heed this information.

The only difference physically of this video card compared to the ATI built Radeon HD 2900 XT we originally tested is a sticker on the fan depicting Sapphire branding. The heatsink and fan combination, and even the flames on the shroud, are exactly the same as the ATI Radeon HD 2900 XT.

If you wish to overclock you will need a power supply with one 2x3 and one 2x4-pin auxiliary power connector per video card. It will however function with just two 2x3 connectors, but you will not be able to overclock.

The software and cable package is very complete. You will find two DVI to VGA adapters as well as the DVI to HDMI adapter. There is also a video in/video out dongle for S-Video and Composite signals. Then there is an HDTV output cable as well. On the software side you get PowerDirector, PowerDVD and installation CD. You will also find a full version of 3DMark06 and the sweetest part of the package, the coupon for the Valve Black Box. The Valve Black Box will include Half Life 2: Episode 2, Portal and Team Fortress 2, that is one awesome box of games.

In all the screenshots above we have two Sapphire Radeon HD 2900 XT videos connected in CrossFire. We have screwed down both video cards to show you what they would look like inside a computer case. In the first screenshot you can see how close they really are with the short CrossFire bridge connectors; there is hardly any room between them. The subsequent picture shows this further. The primary video card simply has no room to intake air and gets smothered by the second video card, which keep in mind is putting off heat from the back of itself, intaking directly to the primary video card.

Even in this open air environment we were concerned about overheating and as you can see put a fan on the intake end of the video cards, to try and get some air blowing between the video cards. We also unscrewed them and pushed apart as far as we can without breaking the PCI-Express slots. The CrossFire bridge connectors are simply too short to allow us to plug the second video card in the third PCI-Express slot on this motherboard.