Urgent question: video cards and Flight Simulator (FS9/FSX)

Sadly, my nice new FS9/FSX PC, delivered 5 days ago, only lasted a few days before it broke down and had to go back to the manufacturer.

While this is very annoying (and not entirely unexpected: I am always unlucky with this kind of thing!), it does give me time to ask whether anybody running flight simulator in Windows 7 64-bit could advise me on a graphics card. I originally had a GTX 460 2GB, but this was giving me all sorts of issues (well documented, apparently) with Level-D and PMDG aircraft in particular, windows opening inaccessibly behind the flight simulator screen and screens going black.

I have the opportunity to change the graphics card whilst the PC is being repaired, and I was thinking (vaguely as yet) of changing to a Radeon XFX HD 5850 1GB. Or possibly 5870. I'm not sure that it is quite such a high performing card, but will be more than good enough for FS9 and probably FSX too. And if it solved the problems I had in the simulator it would be well worth it.

Is anyone with either of theses cards (especially the Radeon HD 5***) able to comment? I marked this urgent because I have to let the PC people know within the next day or two. Any feedback meanwhile would be really appreciated.

Thanks

Martin S.

The problem is described here BTW:

http://forum.avsim.n...to-full-screen/

And this (for FS cognescenti!!) from PMDG support:

"I think it's actually a Windows Driver Model (WDM) problem (which is what's used in Vista and Win7) more than it is an Nvidia problem. I've seen the black screen driver timeout thing happen to FS with an ATI card too. A lot of times it happens when you try to run a program that creates a UAC prompt like Active Sky while FS is running too.

I'm not really sure what to tell you though unfortunately because there's documented problems in XP64 with the GTX 4xx series of cards and FS that probably won't be fixed... FS is just getting too old at this point and MS and the hardware makers don't generally tend to fix problems with old legacy software".

Oh dear, oh dear. Maybe I should have stuck with XP. This could be a very, VERY costly mistake!!!