4850 Crossfire Anti aliasing

[Frizz]

Hey guys,

New parts arrived, installed my new PSU and second 4850. I benchmarked some games and I was just as impressed when I upgraded from ati 9550 to my first 4850.

There's a problem, well I think its a problem, when I put AA up to 8x in Far cry 2 or Crysis the frames would stutter. They slow down only a little but they stutter alot, my CPU is clocked to 3.6ghz so its not from bottleneck. the frames wou8ld show 36-60 but the game would be stuttering to an unplayable state.

Normal?

Resolution 1680x1050

 

[erocker]

Not sure about Far Cry 2 but for Crysis I know that it doesn't use ATi's AA and you'll have to change some things in the games hardware config.
There is some information here that may help you. http://forums.techpowerup.com/showthread.php?t=72178

 

[Frizz]

Thanks erocker, I got one more question though, how come in far cry 2 or crysis the second gpu won't kick in til after a few seconds? It starts as if its only running one card then 10 - 20 seconds later its back to normal 4850 CF fps.

Is this normal?

 

[James1991]

mine do the same, i think its them taking their time switching to 3d clocks when in crossfire.

 

[Hayder_Master]

put the result of FBS

 

[Darren]

Hey guys,

New parts arrived, installed my new PSU and second 4850. I benchmarked some games and I was just as impressed when I upgraded from ati 9550 to my first 4850.

There's a problem, well I think its a problem, when I put AA up to 8x in Far cry 2 or Crysis the frames would stutter. They slow down only a little but they stutter alot, my CPU is clocked to 3.6ghz so its not from bottleneck. the frames wou8ld show 36-60 but the game would be stuttering to an unplayable state.

Normal?

Resolution 1680x1050

I'm not surprised, you've got a 22' in monitor running Far Cry 2 and Crysis which are one of the most graphically intensive games to date which make even the 4870 X2 cry. Knowing this your not content with "ultra high settings" @ 1680x1050 on your 22' LCD you want to add insult to injury by turning on 8x AA!!

When running at 1680x1050 which is a higher resolution than ATI or Nvidia would expect you to run a midrange card anti-aliasing isn't necessary. The entire point of AA is to give the illusion of a higher resolution and 1680x1050 is high enough; at most you'll apply 2x AA for a resolution of 1680x1050, 8x AA is good for people with smaller screen like me that run 19' on 1440x900 or 17' 1280x1024.

Edit:

Hey guys,

the frames wou8ld show 36-60 but the game would be stuttering to an unplayable state.

Normal?

36-60 FPS should be fine for smooth playback, your eyes can not detect low frame rates unless below 20-25 FPS. The stuttering is most probably related to something else e.g. driver issues, remember the 4850 is still new and crossfire support isn't on ATI's list of priorities. Also make sure it's not hard disk related, the stuttering could be due to slow file transfer (maps and textures may be loaded from the HD) - Download Sandra Lite and do a diagnostics of the average hard disk read and write speed as well as a CPU benchmark. Post the screenshots here for us to analyse.

http://www.sisoftware.co.uk/dload/sware_figure.php?langx=en&a=