Why can’t games utilize SLI effectively?

[CatTNT]

Apparently I heard it’s like the single threaded tasks (gaming) vs multi threaded, like video rendering, and game developers just haven’t really coded in good ways to utilize both GPUs. So why can’t there be a program that makes your system recognize 2 or more GPUs as one GPU? Is it impossible? Why couldn’t your system recognize a 2 1080 Tis as one GPu with 7168 core and 22 GB of VRAM?

[saladcrack]

It's possible and there are games that have SLI support but it's the return on investment I think. Spending time on a feature in a game that most of the people playing it will never use is kinda silly.

[SwingLifeAway92]

The main issue is this you're a game developer and made a game that you're now optimizing for the pc market. Do you A) make it so all single gpus work well and get the game out as soon as possible or B) finish optimizing for single cards and then spend another few months on the small percentage of people with multi gpu riggs. Most companies are going to pick A

[xg32]

11 minutes ago, CatTNT said:

Apparently I heard it’s like the single threaded tasks (gaming) vs multi threaded, like video rendering, and game developers just haven’t really coded in good ways to utilize both GPUs. So why can’t there be a program that makes your system recognize 2 or more GPUs as one GPU? Is it impossible? Why couldn’t your system recognize a 2 1080 Tis as one GPu with 7168 core and 22 GB of VRAM?

Most users only have 1 GPU, can't blame devs for focusing on that, drivers are a pain in the ass.

[CatTNT]

You all are right I guess, but why can’t a big non game maker company such as Microsoft make a utility that blends multi GPUs as one and the market it as Multi GPU support for game devs to put in their windows games?

[SnowyMus]

5 hours ago, CatTNT said:

Apparently I heard it’s like the single threaded tasks (gaming) vs multi threaded, like video rendering, and game developers just haven’t really coded in good ways to utilize both GPUs.

Any program may be able to recognize two 1080 Tis. The problem is that they need to know how to use these two processors effectively. Most games don't, and many that do have problems doing so. This takes development time.

 

Quote

So why can’t there be a program that makes your system recognize 2 or more GPUs as one GPU? Is it impossible? Why couldn’t your system recognize a 2 1080 Tis as one GPu with 7168 core and 22 GB of VRAM?

How SLI works is it splits the workload between two GPUs rather than combining two GPUs into one. Combining two graphics cards into one super graphics card wouldn't be very practical for gaming.

 

With graphics cards, RAM is located on the same board as the GPU. Between two graphics cards, the RAM would be very far apart. Sure, maybe you'd have 22 GB of VRAM, but I doubt you would get anything playable out of doing so.

 

As for the CUDA cores, well... Ryzen suffers some loss in performance because its eight cores are split into two quad-core CCs. Thanks to Infinity Fabric, though, Ryzen is still a very fast, viable architecture. However, with two 1080 Tis, the two processors are on totally separate boards and can't simply be combined together. An SLI bridge can at least allow the graphics cards to communicate with each other, but it doesn't combine them together.