I bought a new 5850 and when I plugged it in, turned Crossfire on, updated all the drivers, and updated the bios for both my games run like there is only one. I checked everything and both say they are running fine but the fps for games has no difference. Can anyone tell me the problem and the fix?
Not sure what the problem is, here's what I would look at first:
Make sure in the AMD control panel that Crossfire is enabled.
Make sure the ribbon connector is connected between both cards
To further verify, download a program called GPU-z and run it. It will indicate if crossfire is enabled.
As suggested, check to see if vsync is on, if it is, disable it.
If that still made no difference, I would get weird on it: I would downclock the hell out the cards (like down to 400mhz core speed) and then run games with and without crossfire enabled. If that lets you see a difference between crossfire and not, then there is something forcing vsync on your system.
v-sync will cap your frame rate to what ever your refresh rate is. Most screens now are 60hz so if your frame rate is stuck at 60fps there's a good chance that it's vsync causing your problem and I wouldn't worry about turning it off as it's not really a problem unless your trying to benchmark
Yes I did. Also I did use GPU-Z and everything looks fine. Everything says its fin but I notice no difference.
Just run a benchmark. 3dmark is a free download and will tell you exactly whether or not XFire is working through your score. Run it with XFire OFF and then run it with XFire ON. Compare scores, easy.
Regarding v-sync - yeah it will set an upper frame limit of 60 (on a 60hz monitor). If you are playing games where the minimum FPS isn't dipping below 60 then turn up the settings - you can turn off v-sync for evaluation purposes but having it on is usually best.