Just wondering is it better to leave Hyper Threading off in the bios concerning FS9 or does it enhance the simulator's performance. In a day and aged when manufactures try to sell useless features to make a sell (MMX) that really don't enhance application performance, I'm just wondering is this another market hype that would be better left off versus on on my machine...

Many threads here have discussed it, so a search might do you good.The quick answer is:It has been documented that Hyperthreading neither helps nor hurts performance of MSFS 2004. While Fs2004 was written to "see" HT processors, it was apparently not written to *take advantage* of them. EXCEPION being with one addon (I believe RealityXP gauges) which was coded such that it has serious slowdown issues with HT turned on. I am unsure as to whether or not RealityXP has patched the issue, but users reported by disabling HT on their system, performance of FS2004 returned to comparable levels as those without RealityXP materials.-Greg

Hi,Like Gregg said, HT neither helps nor hinders FS2004 in and of itself. But, because WinXP is made to take advantage of HT it may help if you are running other apps along with FS2004. Such as FSMeteo or ActiveSky, Squawkbox, or Voice Command software. Or you might want to have some doc open for some reason and therefor be running Excel, MS Word, or Adobe Acrobat Reader.For those using HT processors and RealityXP 530 GPS, you can leave HT enabled. But you'll have to take an extra step after starting FS2004.From Phil on Simforums:"A less drastic alternative to disabling HT altogether is to manually set the CPU affinity for fs9 to only use cpu0 instead of the HT cpu0 and cpu1 default.Start fs9 without a default flight or make sure the default flight does NOT load a plane/panel containing the 530xp. After fs9 is loaded up, rightcliick the taskbar, choose taskmanager and then select the Processes tab. Locate the fs9 process, right click it and choose set affinity. Finally uncheck the second cpu1 and say ok. You can now loadup the meridian and garmin trainer without significant framerate loss."Phil.Cheers,Jim

I can't use Flight1's Meridian for that very problem. The Reality gauge problem is horrible. On the flip side, FSMetro doesn't seem to update weather correctly without HT being turned on... RealityXP really needs to patch that problem. I'll leave HT turned on for now.

Well, have you tried the instructions I quoted from Phil on getting the 530XP to work while leaving HT enabled? It works for me. It is the Garmin Trainer which is a 16-bit app that does not like having HT enabled. To be more precise I think it is the 16-bit subsystem of WinXP(ntvdm.exe), which the Garmin Trainer runs on top of, that does not get along with HT.Regards,Jim

I feel this thread needs more specific information for a wise understanding of HT and Reality XP products for one, and FS2004 and windows XP for second.First: ONLY THE GNS530 v2.1 (the latest available for now) requires a special HT aware operation which cures any Windows XP issues with its subsystems.********************************************************************EVERY OTHER REALITY XP PRODUCTS RUN GREAT WITH OR WITHOUT HT IN YOUR CPU!!!********************************************************************So it is not a pandemic issue, but as pointed out in this thread, a more specific issue with the 16bit Windows subsytem.Second, let me remind some facts about this HT technology and let you understand how it could (and not) benefit FS2004 in particular, and windows in general:First, don't expect much from Windows XP Home:==============================================The processor limits which result from this licensing model for 32-bit versions of the Windows Server 2003 family and Windows XP are shown in Table 2.----------------------------------------------------------------Windows Version Maximum Physical Processor Limit Maximum Logical Processor LimitWindows XP Home Edition 1 2Windows XP Professional 2 4Windows Server 2003, Standard Edition 4 8Windows Server 2003, Enterprise Edition 8 16Windows Server 2003, Datacenter Edition 32 32Table 2. Processor Limits for 32-bit Versions of the Windows Server 2003 family and Windows XP----------------------------------------------------------------Also note there are 3 topics covered with HT:=============================================As a result of the HT processor identification support, the following HT-aware features are included in Windows XP and the Windows Server 2003 family.

Thanks guys for the help and info. I now have a clear understanding of HT and FS2k4 and I'm now able to use the Meridian in the sim...

I stand corrected, my computer runs FS better with HT turned off...;-)

After testing out some things here at home I have come away with one conclusion concerning Hyper Threading, it's marketing hype. The only benefit with HT is when one has two physical processors in their machine, even then there seems to be a problem the Hyper Threading reporting the two processors as four separate processors *:-* (go figure). If someone has only one CPU (the majority of us) and has HT turned on (to make their OS/System think two processors are present) has in most cases/applications no performance gain. Even then applications being used need to be programmed to take advantage of the HT features. In some cases performance suffers using Hyper Threading. From my findings with FS2k4, I actually get a sizable performance increase with HT turned off. I don't know if certain add-ons like FSMetro are specially written for to take advantage of HT but I've found trouble with weather updating in FS9. Weather updates fine with Hyper Threading turned on but once I turn it off the sim suffers with close to slid show performance when FSMetro periodically updates the weather while flying in FS9. I can live with this because once the weather is updated (which takes about 10 seconds at the most) the sim is back to normal. Cloud performance has increased with HT turned off as well. I don't get such a performance hit when flying above the clouds. Flight1's Piper Meridian as discussed above doesn't have the performance issues it once had with Hyper Threading turned on. All my other applications and games run noticeably better also without the use of HT as well.All in all for my system it's been best to have Hyper Threading turned off (still testing). Just thought I'd put my findings here concerning FS2k4 which is what this is all about anyway. Wondering what others find...An interesting thing I found with a Xeon processor containing 2 processors is Hyper Threading reports the rig as have 4 separate processors. I don't know but this almost looks like an overall misuse of system resources (the same way it is on a single processor).:-erks Dillon--Dell P4 8300 2.6gig 800FSBRadeon9800 XT1gig SDRAM100 Gig Wester Digital HDWindows XP Pro :-wave

There is nothing wrong at all when Windows reports a hyperthreading machine as having two processors. That's the whole point of HT; one CPU has two logical processors built in. And if you have 2 physical CPUs, then you would have 4 logical processors.I honestly don't believe there could be any performance difference in FS by turning hyperthreading on or off, because as has been explained in the past FS isn't written to take advantage of it. In fact, I would expect performance to drop very slightly with it off since FS as well as any background programs would run off one processor instead of two.-Derek

The only difference, in this ideal HT world, is that there is no 2 CPUs: only one with a better task/thread switching mechanism (including pipeline fill and memory cache management). When a program takes 100% of the CPU, or most of it like FS2004, the task manager showing 50% cpu usage is just an illusion...Furthermore, from the OS perspective, what Windows XP supports of HT is of no use at all in the context of running FS2004, on the contrary, as attempted to be explained above.No doubt HT is great to run dozens of dozens of threads allowing to fill the CPU with activity more inteligently and directly at the CPU level, instead of the OS level (well with the help of the OS though), but try to render a scene with 3DSMAX or convert an AVI to MPEG2 while doing something else...I'm sure it will run as fast (or as slow) than a non HT CPU.Hope this helps!