No, you can't use the PCIe x16 slot and the on board video subsystem. Adding the card will turn off the on board video. There are video cards that support more than 2 displays. Matrox makes cards that support 3, 4, or 8 monitors from the single PCIe x16 slot. There are also PNY cards that supports 4 monitors. There might be others out there but those were the ones I found quickly.
Thats sad to hear! It would be the easiest and cheapest way to extent with a common video card.
What is the reason that the onboard video is disabled when using a PCIe card? Isn't it only an additional video adapter?
Could this be fixed via BIOS?
Motherboards are designed that when an add-in card is being used for video whether PCIe x16, the older AGP and PCI video cards, the on board video is automatically disabled. I haven't seen a board that will allow you both the expansion card and the on board to work simultaneously.
There are boards that have 2 PCIe x16 that would allow you to put 2 individual cards into the computer. You might also find a PCI card that can be added to the system as an additional video card with your PCIe x16 card. But remember this board only has a single PCI slot so if that is the route you go, you will not be able to add another PCI card to the system if you need.
Ok, I see.
But whats the reason from a technical perspecitve that the PCIe x16 slot has to be swichted off, so that it can not work together with the onboard video.
As I found out, it should work (with the onboard video) when using a PCI card. Is that true, and if so, why?
The PCIe x16 is a dedicated video slot and nothing but a video card can go into it. A PCI slot is generic and any PCI card can be utilized. The onboard video utilizes an embedded PCIe x16 slot and this board is only designed to work with a single PCIe x16 device, thus the onboard one turns off. If the board had 2 PCIe x 16 slots the both can be utilized as the board is designed to run with two.
Sorry to jump the thread but, I have the same motherboard in a dual monitor configuration. (both are on the DVIs)
Is is possible to add a third monitor on the Displayport connector ?
Matrox makes a series of video cards that support more monitors. They have a Triple head, Quad Head and even an Octal Head video card. With just one of these cards, depending on which one you choose you can have up to 16 monitors by putting 2 of the Octal head video cards into a single system that has two PCIe x16 slots. With this motherboard you would be limited to a single video card so up to 8 monitors. These are the "M" series cards.