If it's any use, I took some data from Nvidia Inspector during an cloudy/overcast approach into KBOS this morning. NGX VC, Fly Tampa KBOS, AS 2012 with CLOUD_COVERAGE_DENSITY=12, GEX, UTX.

Dazz,I have two GTX 580's, using 285 drivers. I am seeing some flickering on certain objects (maybe you can help with this). I use two monitors in full screen mode both at 1920x1080, but the left monitor is blacked out and I drag items like GPS, Kneeboard, etc to use during game.Comp Specs:i2600k overclocked to 4.5H70 Cooling (Push / Pull Config)ASU Maximus Extreme Motherboard16 GB Corsair Vengeance 1600 Memory2 SSD OCZ Vertez 2 Drives1 SSD OCZ Agility 3 120GB (Max IOPS)WD 7200 1 TB HD2 x GTX 580Win 7 Home EditionFraps for Recording and Track IR 5

Dazz,I have two GTX 580's, using 285 drivers. I am seeing some flickering on certain objects (maybe you can help with this). I use two monitors in full screen mode both at 1920x1080, but the left monitor is blacked out and I drag items like GPS, Kneeboard, etc to use during game.Comp Specs:i2600k overclocked to 4.5H70 Cooling (Push / Pull Config)ASU Maximus Extreme Motherboard16 GB Corsair Vengeance 1600 Memory2 SSD OCZ Vertez 2 Drives1 SSD OCZ Agility 3 120GB (Max IOPS)WD 7200 1 TB HD2 x GTX 580Win 7 Home EditionFraps for Recording and Track IR 5

Those settings are perfect to compare your results with mine. DX9, same resolution, lots of AA, similar hardware...With 16xS + 2xSGSS you should be GPU limited in overcast conditions flying through the clouds. In that scenario my SLI wouldn't work at more than 50% each card in the virtual cockpit and it was all quite choppy.Actually a single card works slightly better for me since I can run this 480 at 860MHz while the SLI topped at 820MHz