First impressions

As we mentioned previously, ATI will be providing three different CrossFire graphics cards initially, the RADEON X850 XT CrossFire, the RADEON X800 XL CrossFire, and the RADEON X800 CrossFire, we’re using the X850 XT CrossFire for our testing. You’ll also need an XPRESS 200 CrossFire Edition motherboard. Here ATI is providing multiple CrossFire SKUs. For Intel users there’s an Xpress 200P CrossFire Edition, which includes an integrated X300-based DX9 integrated graphics core, as well as a discrete Xpress 200 CrossFire Edition chipset. This is the platform we tested on and it’s available for both AMD and Intel users.

ATI has also partnered with Intel to deliver CrossFire to Intel’s 955X platform, at IDF ATI and Intel demonstrated a CrossFire system up and running with Intel’s high-end chipset running flawlessly. ATI could potentially work to bring CrossFire support to other platforms, such as VIA’s chipset solutions or perhaps even nForce4, although it’s doubtful NVIDIA would be interested in allowing that to happen.

Compositing chip

CrossFire up and running

Installation and setup

Setting everything up is a bit different than NVIDIA’s SLI, particularly since the compositing chip removes the need for an SLI connector. Instead you’ll use the CrossFire interconnect cable to hook up the two cards, as well as your monitor. It all kind of works like 3dfx’s pass thru cable back in the Voodoo 2 days. On one end of the CrossFire interconnect cable you’ll find a DMS-59 connection, this plugs straight into the back of your CrossFire Master card. On the other end of the DMS-59 connector is a DVI connection, this is what plugs into your monitor. Finally, hooking off the CrossFire interconnect cable is a second DVI connector, this goes into the secondary (slave) RADEON graphics card.

Just enough space for two X850 XTs

Cards are up and running

Once you understand the connections, you simply plug in both graphics cards (with the CrossFire card required to be installed in the primary PCI-E graphics slot), and hook up the auxiliary power connector. The auxiliary power connector provides a little extra power to the PCI-E graphics slots, and is the same 4-pin Molex power connector you’d use for your hard drive or DVD-ROM drive.

Finally make sure that the dual slot GFX configuration setting in BIOS is set to enabled.

After you’ve finished hooking everything up, you should see an option for CrossFire in the CATALYST CONTROL CENTER. CrossFire is a CCC exclusive feature, so those of you who are still running ATI’s conventional control panel will have to install CCC if you’d like to run CrossFire, at least that’s the case with ATI’s latest driver. Simply click the checkbox to enable CrossFire, and voila, you should be done.

The boards can generate a lot of noise

Here you can see the space between both graphics slots

The CrossFire connector

For those of you who’d like to upgrade in stages, we should also mention that ATI also includes an additional transposer card with CrossFire. This card is for single graphics card operation. The transposer card has to be plugged into the empty PCI-E slot in order to enable all 16 PCI-E lanes to the graphics card. Without the card in place while in single-GPU mode, the motherboard will default to x8 PCI-E lanes (once in CrossFire mode, both graphics cards use 8 PCI-E lanes, just like NVIDIA SLI).