do SLI cards have to match

[RamaX]

Im just about done figuring out the 3 systems im building, one of the last questions is:

Im getting SLI compat vid cards, but only one. If i want to upgrade in future to a 2nd card, does it have to like match or be the same card..??

gracias

 

[Action_Man]

Yes it has to be the same card and preferably of the same brand though with the latest drivers you can use different brands.

 

[pickxx]

It has to be the same model....7800GT with a 7800GT....7800GT will not work with 7800GTX.

But doesn't have to be the same brand....You can use whatever brand you want.

 

[Ned_Flanders]

just to reiterate:

Yes it has to be the same model: i.e 7800GT
With the latest drivers you can use cards from different manufactures.

 

[Turv]

Wouldnt it perform better with the same brand? I.E. 2x XFX 7800GT's.

 

[mpjesse]

Yes it probably would. Manufacturers like to tweak clock speeds on cards. For instance, reference GTX boards are supposed to run at 430mhz. However, most manufacturers will clock them anywhere from 430mhz up to 490mhz. Same goes for memory clock speeds.

When you run two boards with slightly different clock speeds you create a bottleneck. Same principle applies to system RAM.

The most optimal way to run SLI is with 2 identical cards. But as the people above me said, it is not required. Only same model is required.

Not long ago it was required that cards be identical for this very reason: disparity between clock speeds. The new nVidia forceware drivers fix this by adjusting clock speeds to match on both boards.

-mpjesse

 

[offgreen]

It would be nice to know if you'll ever be able to run two different models.

 

[pickxx]

eventually....yes
But who knows when and wht kind of performance it will be