Just be aware that you might have to start some games in single screen mode first, and then choose 5040x1050 in game.
For example, if I start GRID while on a 5040x1050 desktop, it crashes. But if I start GRID while on a single screen (using a profile hotkey to change between triple monitors and a single screen), it loads ok.
For the first run, you then choose 5040x1050 in game, and then the game restarts. For subsequent runs, I always make sure I change the screens to a single screen, then launch the game, which runs in three screens, then back to a single screen when it quits out.
Example:
START - 5040x1050 desktop
- hotkey to one single 1680x1050 screen
- start GRID or other problematic games (I do this also for Left 4 Dead)
- game turns on the outside two monitors and I run the game in 5040x1050
- quit game, returns to single screen desktop
- hotkey back to 5040x1050 desktop
Another thing to consider is that if you have started a game and it accidentally saved the resolution as something other than what your monitors can support, it may also just have a black screen or crash. You may need to start the game in safe mode, or if it doesn't have one, find the config file and return the resolution to default.
As a rule of thumb, I ALWAYS start new games from a single screen desktop first, to save potential heartache.
See if either of those helps you out.
FSX won't show 5040 in DX10 mode....
It works for me, when I force Vsync on in the Nvidia control panel.