MultiGPU Update: Does 3-way Make Sense?

Age of Conan Analysis

The first thing we note here is that AMD leads the benchmark.

1680x1050    1920x1200    2560x1600

Both 3-way SLI and 3-way CrossFire perform very well in this game all the way up to 2560x1600. It looks like the GTX 280 and GTX 285 3-way tests are CPU limited here, but it is odd that the 4870 512MB 3-way solution scores so much lower than the 4850 3-way at 2560x1600 when they've got the same amount of RAM onboard.

1680x1050    1920x1200    2560x1600

Scaling from 1 to 3 GPUs comes in pretty well at 2560x1600 with the 9800 GTX+ and the GTX 260 netting around 140% improvement. the Radeon HD 4870 1GB does pretty well with about 128% improvement. Below the maximum resolution, we don't see scaling much better than 100% (though the GTX 260 and Radeon HD 4850 do manage it).

1680x1050    1920x1200    2560x1600

Moving from 2 to 3 GPUs shows a less impressive picture until we move to 2560x1600 where we see most of the hardware gain some good performance. The Radeon HD 4850 gains near its theoretical maximum at almost 45%. The oddity here is the GTX 260 which shows better performance scaling at lower resolutions peaking at 41% at 1920x1200.

1680x1050    1920x1200    2560x1600

As for value, the two most expensive solutions (the GTX 280 and 285) are pegged at the bottom of the chart. AMD's 4850 3-way shows good performance and good value, especially for a 3 card solution, in Age of Conan. The 4850 3-way doesn't quite reach the 4870 X2 which posts both better performance and better value.

We have 6 configurations that can't post 25 fps at 2560x1600, but some AMD single cards are able to squeak by and it looks as though two card solutions are a better balance of performance and cost than any 3-way option.