I was reading the current issue of Computer Pilot (CP) magazine and came across an interesting article written by Doug Horton. In the article, Horton indicated that extensive testing done by him using the same computer hardware (CPU etc.) showed that FSX framerates using Windows 7 Home Premium 64 were nearly 20 percent higher than when running FSX with Vista Home Premium 64.Horton used an Intel i7-975 cpu and ran the cpu at various clock speeds while testing, and recording, FSX frame rates with FSXMark07 and FRAPS. The results showed a 20 percent increase in fps at any given clock speed. For example, with the cpu running at 3.33Ghz, the test showed an average 40 fps with Vista as the Operating System. With Windows 7 as the OS, the same test with the same hardware and cpu clock speed resulted in an average fps of 48!Horton indicated that a "technical source" told him that this performance improvement was a result of the fact that Windows 7 had the ability to unload a portion of the calculations FSX makes during flights, from the CPU to the GPU. In another article written by Horton in the same issue of CP, he stated that an expert from a well-know component manufacture suggested that Windows 7 includes new API calls that offload FSX graphics calculations from the CPU to the GPU, giving the CPU more resources to crunch numbers for non-graphic calculations. I'm not a hardware guru but this does make sense to me. In my own case, I'm using Windows 7 with an i5-750 running at 2.7Ghz and with Windows 7 Home Premium 64 as the OS. I limit the max frame rate to 22fps and I'm getting very smooth, non-stuttering performance, even when landing at night at a busy airport, which was not the case with my previous system (Core-2 duo @2.4Ghz and Windows XP).

Funny that you should post this, I read the same article the other day. From what a lot of people say here and on other forums, they like Win7 a lot more than Vista, but I am not sure if I have ever seen a direct performance comparison going from Vista to Win7. IF you can get 20% more FPS from that, I would be curious to see what I would get if I went from XP 32 bit with 2GB of DDR2 RAM, to Win 7 with 6GB or more of faster DDR3.

I went from XP 32 bit to Windows 7 64 bit and it took me some time to get to grips with, get used to and resolve problems.I'm not convinced with regard to the 20% gain and the Nvidia drivers for Vista and W7 all seem to be dogs.Vista however was a dog too and perhaps it is rather a case of Vista users experiencing poor performance as opposed to W7 users getting good performance.Just a few thoughts, IAN

I must be really unlucky. I have vista and Windows 7 x64 on dual boot - absolutely no difference in frame rates, not a sausage :(

Well, I'll chime in here. davew_uk you need to eradicate that virus called Vista, and just boot 7. Even though you experience no performance gain in FSX, 7 has a smaller footprint than Vista, and it just runs better.I have seen an increase in FPS since switching over to 7 by at least 5 fps's. I have also gained another 5 just by enabling SLi in my dual 8800 GTX setup.

Well since I already get about a 5 percent boost in performance over Vista with Windows XP, I guess there wouldn't be much of an improvement coming from a Win Xp system to Win 7. It would permit using DX10 mode though, but with all it's visual problems, I'd probably stick to DX9 mode anyway.

Vista definitely runs FSX better for me than XP does, and I use them both to do that, Vista on a laptop and XP on a desktop, although at some point I might get 7 on the desktop, simply as an overall upgrade rather than just for FS.I've not got Win 7 at the moment though, so wouldn't know about whether than does any better again, but it wouldn't surprise me, because Vista is a bit clumsy in my opinion; I think even I could have a go at improving it as an OS, and what I know about writing an OS would comfortably fit on a matchbox. :( Al