Now we have that out of the way we can discuss the actual chipset. The nForce SLI X16 builds on the previous chipset, the nForce 4 SLI. In the previous version, SLI worked by using two X8 lanes instead of two X16 lanes. The ports were physically X16, but electrically, they were only running at X8 each. This was because that’s all the chipset could support, there were only enough lanes for one X16 graphics port and 4 X1 lanes left over, not enough for another X16. So, when you plugged in two X16 graphics cards, they were actually running at X8 each.



Even though this happened, performance was still incredible. But, with the release of nVidia’s new chipset, why would you want one of the old, slower versions? Lets look at some performance benchmarks.

Anandtech featured an article on modifying an nForce 4 Ultra chipset into an nForce 4 SLI chipset, since they are essentially the same chipset with a few minor changes. They compared a true SLI chipset, running both cards at X8, and their modified nForce 4 Ultra running one card at X16 and one card at X2. Now, on paper, this SLI setup looks severely crippled. But, the benchmarks tell a different story.

They confirm what PC buffs have been saying all along: graphics cards simply don’t need all the bandwidth of PCI Express. Sure, performance in some cases dipped by a few frames per second, but the difference is so small anyone can see that X8 for each card is more than enough. X16 for each card is simply overkill.

So, in conclusion, this new chipset from NVIDIA is simply a marketing ploy. They can say they have the best chipset for an SLI setup, and they are right, but it really doesn’t make any difference to your gaming experience. You would be fine with the regular nForce 4 SLI chipset. That's not to say there is anything wrong with the new X16 boards - just don't expect any noticeable gains in performance.

Article by Richard Powell.