How many users have SLI/Crossfire?

[icarus]

Originally Posted by louisv

I have 'used' SLI for years and my personnal verdict is: it generally doesn't work.

If it did, it would almost double every FPS of every supported game and honestly, I have never seen that other than with a special indicator in ROF...And without the indicator, I would not have noticed...so that's hardly double the speed.

And I have all the good (real) flight sims...

Also you buy twice the memory but you don't get it, each card needs to hold the same thing in memory.

If one day I want 3 screens, I'll buy 3 cards and link the desktops, no need for SLI here either.

In short, buy a good almost top of the line card that would have cost the same as two crappy cards and sleep tight.

My two cents.

Lou

PS: What kind of experience do you have with other programs and SLI/Crossfire ?

Not true. SLI works if it is supported by the game. I generally get up to 50% boost. If you get nothing you are probably playing sims that do not support it (FSX, BMS, and older ones do not, RoF and DCS does work). If thesims you have do support it, then you must be doing something wrong (Its not turned on or your bridge is loose or something).

True about the memory.

[6BL Bird-Dog]

@JG52 Krupi
I tested in Default X-Fire with medium settings grass and roads on ,shadows off 87fps vs off ,69fps vs on.
Default X-Fire with V-High settings grass and roads on ,shadows off 45fps vs off ,46fps vs on.
Two Worlds 2 DX10.exe X-Fire with medium settings grass and roads on,shadows off 85fps vs off ,65fps vs on.
Two Worlds 2 DX10.exe X-Fire with V-High settings grass and roads on,shadows off 52fps vs off ,55fps vs on.
Lower altitude settings produce hesitations on all tests but slightly less annoying in medium settings.The rendering looked better in the Two Worlds profile.

@luisv
I started ROF with a single 5870 and when SLI/XFire was enabled got a second one .Performance went up by 50% easily so I upped the eye candy setting and got a nice balance .When I upgraded to a single 7970 the performance improved probably due to the extra memory.Adding a second card allowed me to max out all settings other than Anti-Ailiasing which is always left at 2x as thats the real frame killer.A recent AMD Driver updat introduced flicker of the clouds so I had to cut points of light from max to 15 but otherwise it runs as smooth as silk.

[louisv]

Originally Posted by icarus

Not true. SLI works if it is supported by the game. I generally get up to 50% boost. If you get nothing you are probably playing sims that do not support it (FSX, BMS, and older ones do not, RoF and DCS does work). If thesims you have do support it, then you must be doing something wrong (Its not turned on or your bridge is loose or something).

True about the memory.

Or you hit the cpu bottleneck on your way to complete use of the second card.

I'm not saying it doesn't work at all, I'm saying 'generally doesn't work' not really worth it. I had a couple of GTX9800 with a slightly oc'd quad core and generally with flight simulators, the bottleneck was the cpu...But with a single card too, with the exception of ROF (with the indicator).

Flight sims used to be heavier on the cpu side, that has changed now though, I admit. What gets me with this is that with a given price you get either 2 mid range cards or 1 really good one. About the same price as you do pay twice for memory.

And many games don't support it. Right now ROF and DCS that I'm aware of, with other flight sims, all you are left with is 1 mid-range card..

Lou

[r0bc]

Both ROF and DCS do support SLI however DCS don't scale as well as ROF