Hi,I am currently running the PMDG 737 on a P4 3Ghz machine in hyperthreading. What I would like to know from other P4 users is if I should let the machine run in hyperthreading or not.I thought that in a previous post regarding that matter, some users had to disable the P4 hyperthreading mode because of troubles with the PMDG 737. Personally I have it running in HT from the time it was released and had not one problem with it.Second question is if performance would increase without HT or not. Did anybody try this? I know I could change the BIOS setting to disable HT and do the test, but before doing this, i'd like to poll the forum for other user's experiences in that matter.To summarize:What processor mode will give the best performance? Hyperthreading enabled or disabled? One should think that HT enabled would be best, but we do not really know what goes on behind the scenes, do we?Any comments on this would be greatly appreciated.Best Regards,Jean-Pierre Thirifay

>What processor mode will give the best performance?>Hyperthreading enabled or disabled? One should think that HT>enabled would be best, but we do not really know what goes on>behind the scenes, do we?>>Any comments on this would be greatly appreciated.>>Best Regards,>>Jean-Pierre ThirifayI believe the issues folks have had with HT is when they've upgraded to HT without a complete reinstall of the operating system - apparently XP may not properly support an "upgrade" from a single to multi-threaded CPU.If you've been HT from day one you're probably doing just fine.

Hello Timothy,Thanks for your very fast response and that is what I thought, but we can never do any harm by asking other people's opinions if in doubt.Thanks again,Jean-Pierre Thirifay

Jean-PierreI've tried to run my machine (specs in bottom of post) with both HT ON and OFF. Didn't notice any difference at all!Hope it helps,

Hi, I have also had experience with HT. I noticed a slight perf increase, but I guess the biggest increase, if any, will be for people who are running all the programs on one machine (I am not). I did notice, however, that at times hard drive access seemed to dead lock, so I disabled the HT again.Hope this helps,BoazEKCH