Sapphire Radeon HD 4850 X2 2G GDDR3
As we mentioned at the beginning of this article, Sapphire's take on the Radeon HD 4850 X2 looks nothing like the reference cards we saw pictured during the Radeon HD 4870 X2 launch.
The card you see pictured here is the Sapphire Radeon HD 4850 X2 2G GDDR3. As its name implies, this card sports 2GB of GDDR3 memory (1GB per GPU), but we should note that a 1GB version (512MB per GPU) is also available for a slightly lower price. The pair of GPUs used on the card are clocked at 650MHz, and they're linked to the memory via a 256-bit interface. The memory is clocked at 993MHz (1986MHz DDR).
Although it may be hard to tell by the pictures, the Sapphire Radeon HD 4850 X2 is built upon an extra-long >11" PCB. This is important to consider because this card may not fit in some cases due to its size.
In fact, in our graphics test bed, which resides in a mid-tower case, we had to bend a metal bracket in the hard drive cage to get the card to fit properly.
The Sapphire Radeon HD 4850 X2 2G GDDR3 is cooled by a custom dual-fan solution that essentially covers the entire front side of the card. Heatsinks sit atop each GPU, the memory, and the VRM, and a shroud encases the entire assembly. The fans blow downward through the heatsinks, but air is not expelled from the system because there are no vents in the card's case bracket.
The reason there are no vents in the case bracket is because the Sapphire Radeon HD 4850 X2 2G GDDR3 is equipped with four monitor outputs. Unlike most enthusiast class cards which can support dual independent displays, this puppy can handle 4 (two per GPU). So, although it's designed for gamers, the Sapphire Radeon HD 4850 X2 may also appeal to some pro users who need to push more than two displays as well.
Also note, the Sapphire Radeon HD 4850 X2 is equipped with a single CrossFire edge connector, so a pair of these cards can be linked together for some CrossFireX action--or to power up to eight displays. Just keep in mind, each card requires both a 6- and 8-pin PCI Express power feed, so a powerful PSU is a must as well.