Folks; For those of you running MS Flight Sim on Win XP and an Intel Hyperthreading CPU, here's a truly amazing performance booster:After starting FS, go into task manager (CTRL_ALT_DEL)Select Processes tabRight click on FS9.exe, select "Set Affinity"Disable one of the two check boxes so that FS9 only runs on one virtual CPU (I use CPU 0).Do the same on any other running utilities (i.e. FDC, RC) and select the other virtual processor.I see better than a doubling in frame rates. This, of course, assumes that hyperthreading is supported and enabled on your motherboard and BIOS settings.Thanks to Sean McLeod for this one.RegardsBob ScottATP IMEL Gulfstream II-III-IV-V L-300Washington, D.C

An even better way of constraining FS9 to run on a single virtual CPU on an HT CPU is using the Microsoft IMAGECFG utility (an older NT/2000 utility that works fine in XP -- do a google search). Command syntax (in a Command window):IMAGECFG -a 0x1 fs9.exeThis writes a processor affinity mask into the executable. 0x1 specifies virtual CPU 0, 0x2 specifies vCPU 1, and 0x3 uses both 0 & 1 (default). FS will always run on the specified virtual CPU(s) from that point on.I have done the same to the other utilities I run on the machine while FS is running, only restricting them to the opposite vCPU.Bob ScottATP IMEL Gulfstream II-III-IV-V L-300Washington, D.C

Wow Bob, this is amazing I just doubled my performance, I'm getting steady 50-60 FPS in worst conditions.Thankyou for this great tip.My Simulator system:PC # 1P4 2.8 GHZ 800 FSB HTMotherboard MSI NEO 465PE1 GB PC3500 DDR Corsair XMS RAMHard Drive 80 MB 7200 RPM IDEATI Radeon 9800 Pro 128 MB 4X AA 8X AFVideo Projector Proxima LX1 100" ScreenFlight Simualaror 2004 "Century of Flight"Windows XP Pro SP1.PC # 2P4 1.7 GHZ 768 MB RAMBUS PC-800GeForce 2 GTS Pro 32 MBGeForce 2 MMX 64 MBMonitor # 1 Sony 17" FlatMonitor # 2 Acerview 15"Project Magenta (PFD & EICAS)Windows XP Pro SP1.PC # 3AMD Athlon 1300 XP 512 MB SDRAM PC133GeForce 2 MMX 64 MBMonitor HP 15"Project Magenta (CDU & MCP)Windows XP Pro SP1PC # 4Toshiba Satellite P3 Celeron 1.1 GHZ 256 RAMFsMeteo 6.01, Active Sky 1.9, PM Sounds, FliteStar 8.1 & Jeeppveiw(Jeppesen), SquawkBox 2.3 and Roger Wilco.All PC's are networked with a registered FSIUPC 3.03 & Wide FS.Additional hardware:PFC Jetliner YokeSafeline Jet throttle consoleSaitek Cyborge force feedback JoystickAerosoft MCP

Bob,This is a great find for us with hyperthreading enabled!My performance is MUCH better with this tweak!!Thank YouPaul Cartier

If you don't mind, please post this in the FAQ thread at the top also!Thanks...http://saltydogfly2.avsim.net/images/avsim_sig.jpg"We are the music makers, and we are the dreamers of dreams."

Could you do an additional test? Try disabling HT and see how your performance as you have it now compares with no HT. One might guess that HT enabled machines set up without the tweak may have been way underperforming vs their frequency matched non-HT cousins, since they are dedicating all on one processor all the time anywho.Noel

Bob,I tried it, didn't do anything for me :(

Bob,>Right click on FS9.exe, select "Set Affinity">>Disable one of the two check boxes so that FS9 only runs on>one virtual CPU (I use CPU 0).I'm running my P4 [email protected] GB on an ASUS P4PE.When i right click on FS9.exe task cannot find any "set affinity" tab :-( maybe my MoBo doesn't support that awesome feature? Wich setting should i eventually modify in BIOS to enable that feature?ThanksLuigi ;-)

Luigi,The P4PE is able to make use of HT, but only supports 400/533Mhz P4s CPUs. The only 533Mhz CPU that makes use of HT is the 3.06, you probably have a 533Mhz P4 2.4B, this doesn't support HT.

http://www.tomshardware.com/howto/20030527...adapter-01.htmlJos

John,>I tried it, didn't do anything for meso a CPU upgrade from my actual P4 [email protected] to 3.2 should be useless?BTW, how did you push your CPU to 3.2gb?Every time i try something beyond 2.8 WinXP or FS9 freeze :-( do i need something special?ThanksLuigi ;-)

Ive tried this on a Dell 8300 3.0 h/t, theres no effect at all here.OHN

Thank you!P4 3.2GB can wait..........................In meantime i'm planning to upgrade my TI4200 128mb with a brand new ASUS FX5600 ULTRA 256mb.Now i can run with most slider full right from 25-50 fps (1152x864x32, AA=0, AF=4); only at big airports like EHAM with dense traffic, especially at dusk (STUNNING!!!), my fps go down and also reach 8-9.Should an upgrade worth it?My rig: P4 [email protected], ASUS P4PE, 1MB ram PCI 2100, ASUS V8420 GeForce4 TI4200 128MB.Luigi ;-)

Luigi,I don't think the extra 400Mhz would make any real difference right now. Upgrading to the 5600Ultra wouldn't be a bad move ;) Or you could even try and find a Radeon 9700 Non Pro if you can (and wouldn't mind moving to ATI)These P4 2.4C CPUs seem to overclock quite well (All though its pure luck), the FSB does 250Mhz @ default voltage, little more and I pushed it to 270Mhz. I've got some new PC3700 memory that does 270Mhz 1:1 but my board won't give it mem voltage :(

Thanks a lot Bob,Just wondering if any downside exists with this tweak?Regards,Howard