Wait... Is SLI only useful for 2+ monitors?

[Asthmaboy]

Because you know, I don't see how if there was only 1 screen, it'd be using the second GPU...

The one screen would only be taking up the one port from only one of the cards...

So does using SLI for 1 monitor really matter?

 

[SynthDude2001]

Originally posted by: Asthmaboy
So does using SLI for 1 monitor really matter?

Very much so (in GPU-limited games). There are a few different rendering methods, but the general idea is that the two cards share the workload (either rendering alternating frames, or different parts of the same frame, etc.) and the final image/signal is put together on the "main" card that sends the video to the monitor. Generally the two cards will be directly connected (either internally for Nvidia SLI, or externally for ATI Crossfire).

 

[Matthias99]

Originally posted by: Asthmaboy
Because you know, I don't see how if there was only 1 screen, it'd be using the second GPU...

The one screen would only be taking up the one port from only one of the cards...

So does using SLI for 1 monitor really matter?

Yes, both GPUs work together to render the image on one screen. That would be the entire point of using SLI or Crossfire.

 

[Asthmaboy]

It would seem that they aren't really connected because of the ports that is actually used, but as I don't have a SLI mobo, I can see why I don't know.

 

[Matthias99]

Originally posted by: Asthmaboy
It would seem that they aren't really connected because of the ports that is actually used, but as I don't have a SLI mobo, I can see why I don't know.

They're connected by either the inter-card bridge (for SLI) or the external 'dongle' cable (for Crossfire), and the cards can also communicate across the PCIe bus.

Please go read something about SLI or Crossfire; this is usually explained in excruciating detail in the preview/review articles on SLI/Crossfire.

 

[Asthmaboy]

Yeah, previous to making this thread, I hadn't really thought that they would share the workload through the bus, just kinda thought that they were totally separate entities.
But I was most obviously wrong. D: