Hello all,Two days ago, I decided to put FS2004 & PMDG737 on another machine. I used to run FS2004 & PMDG737 on a P4 1.6G with 512Mb RAM & GeForce FX5200 video. Everything was running fine considering the machine was certainly not one of the fastest to run PMDG, but the aircraft was flyable.This time I installed XP, FS2004 & PMDG on a Athlon XP 2000 machine, fresh install, no addons and ver 1.2 of PMDG because I had no problems with that version on the P4.When I started everything up I noticed that the aircraft was running at half the speed. When advancing the throttles, acceleration went on at half the speed although the indicated airspeed was normal. It took two times the normal time to reach 80knots, V1, VR. Furthermore every flight takes 2 times the normal time to reach from A to B although the indicated airspeed seemed normal. A 450 knots, considering no winds. I also noticed that the ETA on the FMC seemed to constantly increase. A flight from KSEA to KSFO, which in normal conditions would take about 01.30 hours took 03.00 hours to complete. FMC predicted the flight would take 01.30, but while airborne that number kept increasing. The simulation rate was x1. When I increased the simulation rate to x2 everything seemed to be normal except for the FMC clock because time was running twice as fast as normal. Furthermore the FMC has difficulties with rates of more than x1, but that I find is normal. The aircraft was build to simulate real flight conditions and not increased simulation rates.On the P4 I had no problems except that in busy airports the framerate dropped a bit. I thought that I could gain some framerates (not much though) on the Athlon XP, but under these conditions the aircraft is completely unflyable. This is not real anymore.I even tried version 1.3 with same results. Reinstalled XP, reinstalled FS2004, reinstalled PMDG, all with same results.The only thing that is different from the P4 is the motherboard and CPU. The RAM came from the P4, also HD, Video etc...I really do not know what to do anymore. Of course I did not try to do the same flight with the built-in airplanes from FS2004, because I cannot fly them. They are not realistic, I never tried those. The only reference that I have is a real aircraft like PMDG.Could anyone give me a clue on this?Regards,Jean-Pierre Thirifay

Hmm, very strange indeed. It HAS to do with the Simulation rate. Are you really running on NORMAL? --------------------------------Hopefully the first person to buy the PMDG 737-800 :D

Hello, Thanks for you reply sir. Yes, absolutely sure I am running in normal rate. Furthermore I noticed something else.No matter what limit I select for the framerate, the number in the topleft screen displays nearly always my request, no matter what cloudtypes, weather, scenery density. All that does not matter. If I select 30 as limit, i get 29.8, 25 as limit gives me 24.8, always. I clearly see that I do not get 30 or 25 because the I see some stutter, but the number is there. Very strange.On the P4 I saw the framerate change a lot, depending on the outside view, scenery density etc... Like I said, no problems on the P4 except the fact that that machine was not quite up to running FS9 and PMDG without stutter, but al this was flyable.The Athlon XP behaves very strange. All commands seem to go at half the speed. A few moments ago i did some more tests and even braking takes twice the time. Every command seems to take twice the time than normal to execute.I repeat that the only thing I did, was install WinXP, latest videodrivers for FX5200, 56.64, installation of PMDG 1.2 and nothing else. No other addons like other version of FSUIPC etc..., just the installation like I did numerous times on the P4. It goes flawless and everything from the first time except that now on the Athlon everything seems to go at half the speed with simulation rate normal (x1), although the FMC clock is following realtime.If you ask me, I think it has something to do with a timer that is not read correctly, but who am I. I get no errors, nor from Win, nor from drivers, everything is running, but at half the speed.Regards,Jean-Pierre Thirifay

Are you sure this is ONLY with the PMDG add-on? Did you try it with the Defaults at all? A really weird problem, but I don't see a reason why it should be occuring because of WinXP or your Athlon!? I cannot make anymore suggestions, let's leave it to the experts...---------------------Hopefully the first person to buy the PMDG 737-800 :D

This is probably a stupid question, but I'm an expert at asking stupid questions. You stated that it was a fresh install, did you install the latest FSUIPC? Not sure if that would cause the problems you are having, also, could you, for the sake of troubleshooting, slum it a little and try a default aircraft? This will determine if it is an FS problem or a PMDG problem.ThanksChuck CYXU