Compared to our results from the past, our Linux SLI results using two 8600GT graphics cards and the 100.14.19 driver are quite impressive. NVIDIA's SLI was the biggest benefit in Quake 4 when using the Alternate Frame Rendering (AFR) mode as opposed to Split Frame Rendering (SFR) mode. In some cases, the SLI AFR results were almost double of the single GPU Linux results. However, when comparing these numbers to Windows, there is still very much a performance delta between the two operating systems on the latest GeForce 8 hardware. In some of the benchmarks, a single GeForce 8600GT running in Windows was faster than two GPUs running in Scalable Link Interface under Linux. The single GPU improvements in the latest driver are quite nice and the benefits of SLI under Linux are becoming noticeable, but without a doubt it's running much slower than Microsoft Windows with their 162.18 WHQL driver.
What have your experiences with SLI under Linux or Solaris been like? Tell us in the Phoronix Forums.