If you have an HP laptop such as my EliteBook 8570w, you might have run into this issue when trying to hook up external monitors to the computer. The laptop has its own LCD display, as well as an external VGA connector and a DisplayPort plug. If you hook it up to an HP Docking Station such as the HSTNN-I10X (a.k.a. HP Advanced Docking Station Port Replicator) it looks like you can connect even more, as the docking station has a VGA port, 2 DVI ports and 2 DisplayPort ports). If, however, you try to pull this off, the HP does detect all the screens but will spit out “The display settings could not be saved. Please try a different combination of display settings":
This makes it sound like some kind of driver or firmware problem, but don’t run off installing software, because it won’t help. The cause of this issue isn’t in the software, but due to the way the docking station is designed. You see, even though the docking station has 2 DVI ports and a VGA port, it can’t put a picture out to all of them at the same time. You can output to VGA+DVI or DVI+DVI…but that means turning off the laptop’s own LCD display (in other words…two screens together and no more).
If one or more of your monitors is new and has a built-in DispayPort input, then you can hook it up to the Docking Station’s DisplayPort, and then you can use 3 monitors (the built-in LCD, one DisplayPort monitor and one DVI/VGA monitor). Using the DisplayPort output, you can even hook up 4 screens (the HP’s LCD, two DisplayPort monitors and one VGA).
“But the HP laptop comes with a DisplayPort to DVI adapter”, you say? True, but HP were just too cheap to bundle a decent one. DisplayPort is very close to DVI and HDMI, technically, but it’s not quite the same. The adapter that comes with the computer is a “passive” one, which means you cannot use it for this purpose. The adapter you need should be “active”, and you can find plenty of them on Amazon, starting at about $15. For example, this adapter by Cirago is for a VGA screen:
This one is for DVI (a little more expensive):
So, HP were able to shave off $5 off the cost of your $2000 computer and prevent you from using a 3rd screen, and to make it worse, make their documentation virtually impossible to understand this simple fact. I’m not sure who’s responsible for the meaningless message about the settings that cannot be saved, but that sure doesn’t make me feel better. At least now we know what to do…either get DisplayPort capable monitors, or the active adapter!