The SLI driver issue
I mentioned in the first article that the early drivers for SLI had a habit of changing the SLI mode, and dramatically changing performance even if the SLI mode remained static, between revisions. Despite the driver's other faults, that basic changing of modes made it hard to pin down performance initially. Here's an example to show you what I mean. I've taken the 6800 Ultra SLI Doom3 scores from the initial article, using 66.93 and the driver using AFR, and plotted them against 6800 GTs using 66.75 and SFR.
As you can see, 66.75 with SFR on GTs has the same performance as Ultras using 66.93 and AFR. And AFR is actually the faster mode. Forcing it in 66.75 makes the GTs even quicker. It's clear that since 66.75, Doom3 has lost some performance in both the mode switch and the driver revision, for (as far as I can make out) the same image quality. However, with 66.75's performance issues in other games titles, 66.93 is the driver of choice for all comparative testing.
So just a quick page to help hammer home the fact that the driver still holds the key to performance and that performance can, and most likely will, go up or down in future revisions.
