$5400K alienware during T-Strms/Flooding. Insurance will cover minus some depreciation (2yr system). Luckily all my software/addons etc, are saved on an external HD. If you could pick an OS to run FS9 and FSX what would it be? I'm looking at a replacement system with 12GB DDR3 RAM and intel i7 extreme overclocked to 3.6Ghz--2x ATI Radeon HD 4870 (2GB) GPU, etc.I ran FS9 exclusively with the Alienware and Win XP Home 32-bit and 4GB RAM (though it was limited to 2GB), Nvida GX2 7950, and an AMD FX-60 CPU, and was very happy with the performance. I dabbled in FSX early on but was disappointed with low FPS with add-on weather (AS6.5), lack of addon complex aircraft, etc.Some questions:Win XP Professional 64-bit limits recognized RAM but is a good choice for FS9/FSX?If I go Vista, what version works the best with FS9/FSX and does it recognize all the RAM?Would you go with the new ATI card or go with Nvidia?ThanksR.Perry

I run Vista 64bit and do not regret it at all....

$5400K alienware during T-Strms/Flooding. Insurance will cover minus some depreciation (2yr system). Luckily all my software/addons etc, are saved on an external HD. If you could pick an OS to run FS9 and FSX what would it be? I'm looking at a replacement system with 12GB DDR3 RAM and intel i7 extreme overclocked to 3.6Ghz--2x ATI Radeon HD 4870 (2GB) GPU, etc.I ran FS9 exclusively with the Alienware and Win XP Home 32-bit and 4GB RAM (though it was limited to 2GB), Nvida GX2 7950, and an AMD FX-60 CPU, and was very happy with the performance. I dabbled in FSX early on but was disappointed with low FPS with add-on weather (AS6.5), lack of addon complex aircraft, etc.Some questions:Win XP Professional 64-bit limits recognized RAM but is a good choice for FS9/FSX?If I go Vista, what version works the best with FS9/FSX and does it recognize all the RAM?Would you go with the new ATI card or go with Nvidia?ThanksR.Perry

You might want to wait a few weeks, as the new rev d0 intel CPUs should be hitting the streets, and if you're gonna spring for a $1000 CPU, the new i7 975 will be along to replace the i7 965 extreme soon. That said, you can OC a $280 i7 920 to 3.6 GHz for a lot less...folks are running the new d0 920s at 4+ GHz now.I run 64-bit Vista for FS...it rocks once you shut off the oppressive security crap like UAC, Defender etc.Not sure what purpose 12 GB of RAM is intended to serve (certainly none for FS), but any 64-bit variant of Vista or Win 7 (now in public beta) will see all 12 GB. From a speed perspective, 6 GB (3x 2GB DIMM) will be faster, as you have to slow down the RAM timings with a second bank of DIMMs. FS9 and FSX are both 32-bit programs, so neither will be able to use more than 4 GB under any circumstances.nVidia is King for FS, and holds its own quite nicely on vertex-based 3D games like Crysis. I'd go with a GTX 285, or if dual GPUs is desired for other non-FS apps, a GTX-295 (2 GPUs in one package). Neither FS9 nor FSX can make use of dual GPUs.RegardsBob ScottColonel, USAF (ret)ATP IMEL Gulfstream II-III-IV-VColorado Springs, CO

win xp 64 should be decent, also scrap that ATI card, get a single GTX285, eVGA or other major brands

You might want to wait a few weeks, as the new rev d0 intel CPUs should be hitting the streets, and if you're gonna spring for a $1000 CPU, the new i7 975 will be along to replace the i7 965 extreme soon. That said, you can OC a $280 i7 920 to 3.6 GHz for a lot less...folks are running the new d0 920s at 4+ GHz now.I run 64-bit Vista for FS...it rocks once you shut off the oppressive security crap like UAC, Defender etc.Not sure what purpose 12 GB of RAM is intended to serve (certainly none for FS), but any 64-bit variant of Vista or Win 7 (now in public beta) will see all 12 GB. From a speed perspective, 6 GB (3x 2GB DIMM) will be faster, as you have to slow down the RAM timings with a second bank of DIMMs. FS9 and FSX are both 32-bit programs, so neither will be able to use more than 4 GB under any circumstances.nVidia is King for FS, and holds its own quite nicely on vertex-based 3D games like Crysis. I'd go with a GTX 285, or if dual GPUs is desired for other non-FS apps, a GTX-295 (2 GPUs in one package). Neither FS9 nor FSX can make use of dual GPUs.RegardsBob ScottColonel, USAF (ret)ATP IMEL Gulfstream II-III-IV-VColorado Springs, CO

BobThanks--since I've not used Vista--besides defender and UAC what else have you turned off or modified? And, how do you go about doing it? Also, if there are any other Vista v FS9/FSX tweaks please let me know (shoot me an email). R. PerryColonel, USAF (ret)Montgomery, AL

Tweak your system using this guide:http://www.simforums.com/forums/forum_posts.asp?TID=29041