My FS9 setup is presently on a HDD with Win XP SP3 32 bits. I am dealing with a number of OOM CTD, caused by complex aircraft add-ons, which I would like to eliminate (although I have the 3GB switch installed). To avoid a full reinstall of FS9 with a massive number of add-ons (sceneries and planes) I was advised to buy another SATA HDD on which I would install Win 7 Premium 64bits and create a shortcut for FS9 on this new drive and OS. Does this sound like a logical step? My PC is an Asus PT6 Deluxe Intel I7 940, 4GB RAM, ATI Radeon 4870 1GB.Last question, which drive should I install MCE, REX and ASE which are all running in sync with FS9?Thank you for your help.

Keep in mind that many addons keep their settings in registry, all payware addons etc. Without those many won't work at all. Also those programs like ASE, REX etc. FS9 ITSELF will work in another OS without reinstall though. You might need registry fix from Flight1 (google) to fix the FS9's path for addon installations.All that said, I would HIGHLY recommend FS9 reinstall with all its addons when you put W7. Porting mostly causes more pain than it solves.And also, if you still have OOMs while having /3GB switch AND having FS9.exe application changed for high memory usage, then you will probably have the same problem under 64bit OS, since it only gives 1GB of memory more, and your problem is that the usage goes over 3GB. It *might* be enough (4GB in 64bit OS), but the problem will persist if a scenery error or the aircraft is pushing the usage over 4GB.Hope that helps.

Many thanks Word Not Allowed for your advice. I did suspect some drawbacks with this "shortcut". As I have many add-ons from PMDG and Flight One, I may run into snags again.Now in your message you mention FS9 changed for high memory usage, I frankly do not remember having done that and do not have the slightest idea as to how verifying it and/or implement it. Would you care to point me in the right direction please, my search on this forum returned no target topic?Once again thank you for your precious input.With best regards,

If you added /3GB switch and did not change fs9.exe to use it, you didn't change a thing.Anyway, you need to do this:CFF Explorer http://www.ntcore.com/exsuite.php - File Header / Click Here / App can handle >2GB... check, save the file.Along with /3GB, you will allow the fs9.exe to use more than 2GB, in this case up to 3GB of virtual space. 64bit OS would allow you to use 4GB in this case.

Thank you again Word Not Allowed, I will check that.Warmest regards,