Mixing different GTX670 cards in SLI?

[ed79]

Currently I'm running a single KFA2 reference design 670 with blower cooler. I'm considering getting a 2nd to SLI but am not sure whether to go for another identical KFA2 or pre-order the MSI twin fan one.

I'd prefer another blower as I understand these work better in SLI, but the MSI is the same price and runs faster as it's factory overclocked.

Also, if you SLI two different speed 670s does the faster one slow down to match the slower one?

Thanks.

 

[Gripen90]

Currently I'm running a single KFA2 reference design 670 with blower cooler. I'm considering getting a 2nd to SLI but am not sure whether to go for another identical KFA2 or pre-order the MSI twin fan one.

Go for which one you like better. It doesn't matter and they don't have to be identical. Only the GPU and amount of VRAM must be the same

I'd prefer another blower as I understand these work better in SLI, but the MSI is the same price and runs faster as it's factory overclocked.

Again go with the one you feel most for. Reference/Non-reference doesn't matter, it's just about looks inside the PC case.

Also, if you SLI two different speed 670s does the faster one slow down to match the slower one?
Thanks.

No this was the case with SLI and CrossFire 5 years ago. In 2009 nVidia changed the driver support to allow different clocks speeds on mixed multi gpu platforms. Each card runs with their individual clock speeds.

 

[Final8y]

No this was the case with SLI and CrossFire 5 years ago. In 2009 nVidia changed the driver support to allow different clocks speeds on mixed multi gpu platforms. Each card runs with their individual clock speeds.

It was never the case with CrossFire, i was running different clocks on the 1900xts

 

[Gripen90]

It was never the case with CrossFire, i was running different clocks on the 1900xts

Ya you're right. I'm mixing things up back then where you had to have a CrossFire Edition card and a "standard" card to run CrossFire.

 

[ed79]

. In 2009 nVidia changed the driver support to allow different clocks speeds on mixed multi gpu platforms. Each card runs with their individual clock speeds.

Ah that's interesting, I didn't know that. Looks like the MSI will be better then, but won't its cooler increase the heat in my case on top of having 2 Gfx cards close together?

I remember on the origial 670 thread when the cards were released that people found 2 Windforce cards together caused the top one to run over 10 degrees hotter for example. I do have a Silverstone FT02 and so neither card will actually be "on top".

I prefer the idea of the air being vented outside my case, but has anyone tried both types of cooler and if so how much difference does this make?

 

[Gripen90]

Ah that's interesting, I didn't know that. Looks like the MSI will be better then, but won't its cooler increase the heat in my case on top of having 2 Gfx cards close together?

I remember on the origial 670 thread when the cards were released that people found 2 Windforce cards together caused the top one to run over 10 degrees hotter for example. I do have a Silverstone FT02 and so neither card will actually be "on top".

I prefer the idea of the air being vented outside my case, but has anyone tried both types of cooler and if so how much difference does this make?

I have tried both types and there are pro's and con's with each.

The blower style fan (radial fan) is great for PC cases the aren't well ventilated and have restricted airflow. Here the heat from the GPU is dissipated outside the case and not heating up other components in the system e.g like CPU, HDdrives, Ram. Also when running SLi with 2 or 3 card with very narrow spacing the cooler will still perform admirably and cool the cards decently and exhaust the hot air.
The downside is that the radial blower style cooler doesn't deliver the best cooling which is usually important for overclockers, nor are they particularly silent when the cards is running in load.

Cards with at 3rdy party cooler like windforce,acx,twinfrozr are superb coolers that usually cool the GPU better than the radial cooler and allows lower temperatures, better overclock and less noise in load.
The down side is that this type of cooler exhausts all the hot air from the GPU into the case, and it's therefore imperative to have good case cooling to get the hot air outside of the case again.
Also I running 2 cards in SLi it's best to have a motherboard that allows some spacing between the two so they can breath. Putting 3 cards together with 3mm clearance is just asking for temperature problems and crashes.