[SOLVED] Is SLI stupid?

nyxanna

Distinguished
Apr 16, 2011
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I keep reading that SLI is outdated and stupid but when I look at benchmarks it looks like you do need SLI if you want to run games like The Witcher 3 at very high frame rates at 4K.

I have not kept up but is SLI still relevant? I even read that some games don't run unless you turn SLI off which is a big turn off.
 
Multi-GPU setups are becoming obsolete and dead ! Not many GAMES even scale well properly on an SLI or CFX setup.

But, you must be aware that NVidia has introduced a new interface called NVLINK with the consumer Turing GPUs, instead of the old SLI. Obviously, it's the same multi-GPU bridge which can be used for gaming, but it has an interface with many times the bandwidth of an SLI connection.

Because NVLink can be used for direct memory access between cards, and not through the PCIe slots as this was creating a huge bottleneck with SLI. So I think NVlink is the future, if we go by Nvidia's theory,

But I could be wrong though, because not many Games might be able to reap the full benefits of NVlinK, because the same thing happened with SLI. SLI bridges mostly used to have a bandwidth of 1GB/s (normal bridge), and 2GB/s (for the HB bridge), with a rough estimate. NVLink on Turing cards can do 25GB/s one way, and or 50GB/s in total. But according to Nvidia, total bandwidth is 50GB/s one way, and 100GB/s total.

But all of this will only help, if GAMES are going to take advantage of this new multi-GPU feature, provided the Game developers also implement this.

I think the main advantage of Nvlink is that it might help with peer-to-peer interface, VRAM stacking, because essentially the GPUs are much closer together now, also bringing the latency of a GPU-to-GPU transfer way down.

So unlike SLI, where the latency had to go through PCIe as well as memory, Nvlink behaves in a different manner. We can think of it an app that looks at one GPU, and then looks at another GPU and does something else same time. So it seems NVlink will be the future when it comes to multi-GPU setup, but sadly ONLY on the high-end market segment, as other Turing cards will lack NVLINK support.

But again, like I said before, all of this will actually depend on how well the Game's ENGINE benefits from a future multi-GPU setup. Apart from this, even the price of an NVLINK bridge is kind of high, so this can be a very expensive multi-GPU setup, and not many gamers might be able to afford these.

I STILL prefer having a SINGLE powerful GPU on my rig, because a lot of games don't scale well on SLI/CFX. Can't comment about the performance of NVlink though.
 

Lutfij

Titan
Moderator
If you want numbers, then yes you're right to go with SLI. If you're looking for real world performance and games that can benefit SLI/multicard setups, then you're wasting your time looking for it in the form of SLI/Crossfire.

I'd personally suggest getting the single most powerful card that your wallet and your system can handle(including the PSU output). Nvidia have stated that if the devs don't implement SLI technology in their games, we won't force them to. In fact implementing SLI for games takes resources.
 
Reactions: Mandark
Multi-GPU setups are becoming obsolete and dead ! Not many GAMES even scale well properly on an SLI or CFX setup.

But, you must be aware that NVidia has introduced a new interface called NVLINK with the consumer Turing GPUs, instead of the old SLI. Obviously, it's the same multi-GPU bridge which can be used for gaming, but it has an interface with many times the bandwidth of an SLI connection.

Because NVLink can be used for direct memory access between cards, and not through the PCIe slots as this was creating a huge bottleneck with SLI. So I think NVlink is the future, if we go by Nvidia's theory,

But I could be wrong though, because not many Games might be able to reap the full benefits of NVlinK, because the same thing happened with SLI. SLI bridges mostly used to have a bandwidth of 1GB/s (normal bridge), and 2GB/s (for the HB bridge), with a rough estimate. NVLink on Turing cards can do 25GB/s one way, and or 50GB/s in total. But according to Nvidia, total bandwidth is 50GB/s one way, and 100GB/s total.

But all of this will only help, if GAMES are going to take advantage of this new multi-GPU feature, provided the Game developers also implement this.

I think the main advantage of Nvlink is that it might help with peer-to-peer interface, VRAM stacking, because essentially the GPUs are much closer together now, also bringing the latency of a GPU-to-GPU transfer way down.

So unlike SLI, where the latency had to go through PCIe as well as memory, Nvlink behaves in a different manner. We can think of it an app that looks at one GPU, and then looks at another GPU and does something else same time. So it seems NVlink will be the future when it comes to multi-GPU setup, but sadly ONLY on the high-end market segment, as other Turing cards will lack NVLINK support.

But again, like I said before, all of this will actually depend on how well the Game's ENGINE benefits from a future multi-GPU setup. Apart from this, even the price of an NVLINK bridge is kind of high, so this can be a very expensive multi-GPU setup, and not many gamers might be able to afford these.

I STILL prefer having a SINGLE powerful GPU on my rig, because a lot of games don't scale well on SLI/CFX. Can't comment about the performance of NVlink though.
 

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