It's no secret that Nvidia SLI is basically dead for games and graphics cards. While Nvidia supported NVLink on the RTX 2070 Super, 2080 Super, and RTX 2080 Ti, it was never really worth it from a performance perspective in gaming due to underwhelming scaling. Now, with the RTX 30-series cards based on the Ampere architecture, Nvidia is dropping NVLink on all cards but the top-tier GeForce RTX 3090.
Normally, we'd be upset at a development like this, but now it doesn't really seem to matter. A few generations ago, it was still easily possible to overwhelm even the best graphics cards with the games of that time, but if Nvidia's promises are true, we shouldn't need more power than what the GeForce RTX 3070, GeForce RTX 3080, and particularly the RTX 3090 can provide by themselves.
If the RTX 3080 can power 4K gaming at high framerates and ultra settings, do you really need more GPU power? With the RTX 3080 packing 8704 CUDA cores, and the RTX 3090 a staggering 10,496, probably not — especially with the developments in DLSS, Nvidia's AI-powered upscaling technology. At least not for gaming purposes.
The RTX 3070 is supposed to be faster than the RTX 2080 Ti, and the RTX 3080 is double the RTX 2080 performance. Plenty of games already run into CPU bottlenecks at 1080p, and with even faster graphics cards coming, 1440p will be in a similar state on Nvidia's top two GPUs. Doubling down on the RTX 3080 would probably only yield a 25% boost in performance, and that's still only in games that support multi-GPU.
How many demanding games of the past two years have even bothered with multi-GPU support? None of the ray tracing enabled games have done so, and even games that have SLI profiles (e.g., Star Wars: Jedi Fallen Order) had questionable results. Slightly higher average performance but with substantially worse minimum fps means lots of microstutter. It's not a great experience, and the amount of developer effort required to get it working properly is generally more than publishers are willing to invest.
Of course, if you're dead-set on an NVLink setup, it's not entirely impossible. You'll need two RTX 3090's and an NVLink bridge for $79, bringing the total price tag to an eye-watering $3077. Plus tax.
Getting more GPU power isn't just about gaming, of course. If you're running GPU compute algorithms, doing AI research, or other non-gaming work, a pair of RTX 3090 cards might be just what you need. That's why Nvidia's DGX A100 comes with eight A100 GPUs linked up via NVSwitch. It's why Intel's Xe HP and Xe HPC will be able to scale compute performance nearly perfectly by adding additional GPU tiles. The difference is that such workloads aren't normally done in real-time, requiring synchronization between display updates down to the millisecond.
We've generally stopped bothering with multi-GPU benchmarks in games, simply because it's a rarity for it to work without headaches and fiddling. Having two GPUs in your gaming rig will even reduce performance in many games. If you're hoping to break benchmark records in 3DMark, yes, multi-GPU will help. But for regular games? It's just not worth the hassle.
