In terms of benchmarks between the Nvidia GeForce GTX 1080 Ti and Nvidia GeForce GTX 1080 Sli, the 1080 Sli provides slightly higher FPS (frames per second) for most games. But, sadly enough, 1080 Sli does not help in most cases where it should.
From a general perspective of 1080 Ti vs 1080 Sli Benchmarks, the GTX 1080 Sli should offer much better performance than a single GTX 1080 Ti card. But it does not provide the performance a user expects. In some cases, frame rate results are worse on 1080 Sli than a 1080 Ti.
Nvidia GeForce GTX 1080 Ti vs 1080 Sli Benchmarks – How Is It?
Although 1080 Sli offers higher FPS for most of the games. The results taken from some games are shown below:
Assassins Creed Origins
GTX 1080 Ti offers an average frame rate of 48 FPS, minimum 45 FPS, maximum 53 FPS at 3840×2160 resolution, and ultra graphics settings. And at 1920×1080 resolution and ultra settings, this card offers an average frame rate of 92 FPS, minimum 75 FPS, maximum 118 FPS.
On the contrary, the GTX 1080 Sli offers an average frame rate of 38 FPS, minimum 13, maximum 61 at 3840×2160 resolution, and ultra settings. And at 1920×1080 resolution and ultra settings, the game runs at an average frame rate of 72 FPS, minimum 58 FPS, maximum 148 FPS.
From the above result of Assassins Creed Origins, you can see the GTX 1080 Sli is providing less FPS than the 1080 Ti. It also shows the game has more frame drops and stutters than 1080 Sli.
In Battlefield 1, we see that the GTX 1080 Ti has an average FPS of 73, minimum 66, maximum 85, 1% of 53, .1% of 43 at 3840×2160 resolution, and ultra settings. And at 1920×1080 resolution and ultra settings, the average frames per second is 140, minimum 126, and maximum 155.
On the other hand, the GTX 1080 Sli can give you a standard FPS of 79, minimum 73, maximum 88, 1% of 43, .1% of 38 at 3840×2160 resolution, and ultra settings. Whereas at 1920×1080 resolution, ultra settings, this shows an average of 154 FPS, minimum 121 FPS, maximum 177 FPS.
In this test, results show that GTX 1080 Sli offers slightly higher FPS in Battlefield 1. But for two of the 1080s, the numbers are quite disappointing. Here you can see the frame drops are still visible.
Rise of the Tomb Raider
GTX 1080 Ti offers 36 FPS on average, minimum 30, maximum 39 at 3840×2160 resolution, and very high settings on Rising of the Tomb Raider. At 2560×1440 it offers 64 FPS on average, minimum 49, maximum 72.
But 1080 Sli rendered the game at an average of 89 FPS, minimum 59, maximum 94 at 3840×2160 resolution. Again, at the resolution 2560×1440, the average FPS is 150, minimum 82, maximum 183.
The result of Rising of the Tomb Raider shows that the performance of 1080 Sli for this game is noticeable. But in reality, the stutter and frame drops are still visible on 1080 Sli.
Test System Specs
Although the three games are not rendered on a single computer, all the PCs were beyond the requirements of the games. To be specific, all the CPUs had more than 6 cores and 12 threads, RAMs were more than 12 GB and the storage was SSD (Solid State Drive). Windows 10 64-bit has been used as the operating system.
Issues of GTX 1080 sli
For $1200, using GTX 1080 Sli instead of a GTX 1080 Ti for $700 is not worth it. Here you will upgrade your rig by spending $500, the performance is not noticeable at all. Additionally, frame drops and stutters are a common problem for 1080 sli.
How Many GPUs are Supported by GeForce GTX 1080 Sli?
GeForce GTX 1080 Sli supports up to two GPUs by default. Nvidia does not recommend 3-way or 4-way sli modes.
In 2016, to build the most powerful gaming pc no matter what the price is, it would have been valid to get GTX 1080 Sli. But in 2021, taking 1080 Ti vs 1080 Sli Benchmarks into account, it is better to have a GTX 1080 Ti rather than upgrading your rig with GTX 1080 Sli.