Hi there fellow flight simmers.I feel totally and utterly bemused by the situation I find myseft in. I am currently running a Core 2 Duo E4500 OC to 2.67GhZ, 2gb OC 990MhZ DDR 2 RAM, and have recently upgraded from a nVidia 800gs to a ATI HD4850 graphics card.Now with my old 8400gs I was getting a solid 16-20fps whilst flying off one of my save game files. I have now upgraded to the HD4850, updated using the latest catalyst drivers off ATI's website, and I then got about 8fps??? :( According to the tomshardware benchmarks the 8400gs should be at 4fps, and the HD4850 at 24fps for example, 6 times quicker, but its now twice as slow. Please guys, I've done a fresh install of xp, defragged, FSX, Sp1 and Acceleration, no addons and my situation is still the same. Has anyone got any advice as to what is happening and how I can fix it. Not only that but I seem to be experiencing some artifacts as well. Could it be that my GPU is not getting enough power, it is a factor that concerend me when I bought the card. Having said that all my other games including ARMA armed assualt are running perfectly and much much faster.Please help FSX experts!Thanks!

It's been reported by many that ATI cards run slow when 3D clouds are used in FSX.Try setting weather to clear and see if thats your issue.

Hi there and thanks for the reply. I've attempted setting clouds to simple as well as weather to clear. Seems to be a more fundamental problem than that. Unfortunetly that didn't make much of a difference, but thanks for the advise. Any and all suggestions are welcome.

Hi there fellow flight simmers.I feel totally and utterly bemused by the situation I find myseft in. I am currently running a Core 2 Duo E4500 OC to 2.67GhZ, 2gb OC 990MhZ DDR 2 RAM, and have recently upgraded from a nVidia 800gs to a ATI HD4850 graphics card.Now with my old 8400gs I was getting a solid 16-20fps whilst flying off one of my save game files. I have now upgraded to the HD4850, updated using the latest catalyst drivers off ATI's website, and I then got about 8fps??? :( According to the tomshardware benchmarks the 8400gs should be at 4fps, and the HD4850 at 24fps for example, 6 times quicker, but its now twice as slow. Please guys, I've done a fresh install of xp, defragged, FSX, Sp1 and Acceleration, no addons and my situation is still the same. Has anyone got any advice as to what is happening and how I can fix it. Not only that but I seem to be experiencing some artifacts as well. Could it be that my GPU is not getting enough power, it is a factor that concerend me when I bought the card. Having said that all my other games including ARMA armed assualt are running perfectly and much much faster.Please help FSX experts!Thanks!

I wouldn't think that the 4850 would have any problems with clouds because of the newer driver releases. My 4870 runs FSX like a banshee. What video card driver release are you using?In the CCC there is a slider, move it all the way to the left and then all the way to the right, and then apply. In the sim have TriLinear and AA selected.Check your other fsx options, you might have some setting to high for your cpu/memory to handle.Don't make any other changes, and try running the sim.Note that your cpu and memory are a bit on the slow side.

As of 9.4 my ati cards ran fsx like crap. I ditched them for a gtx 285 and couldn't believe the difference in fsx and other games. Clouds would literally KILL my performance. I find it difficult to believe that ati fixed their drivers to work better with fsx the day after I leave for nvidia (hyperbole) since they would never do it before. It has just been my experience that if you are a simmer then stay far far away from ati. Nothing makes me believe that this has changed. I did however get excellent smooth performance when weather was clear so if you are not getting good performance when weather is clear then you may have another problem.

I am locking this thread.Normally I should delete it.Please comply with Avsim's rules:http://forums1.avsim.net/index.php?showtopic=64276Thx