How can I use a DVI splitter cable on 1 DVI port?

I have a GTX 275 video card with 2 DVI ports. I already run 2 monitors, but I've seen cables that plug into one DVI port and split into 2 more connectors.

Is there some special trick to getting this to work with my card so I could have up to 4 monitors running? I don't really want to buy the adapter until I know that it will work (or not work as it may be).

Solution 1:

Unfortunately a splitter will just mirror the display on 2 monitors. You will need something like the dualhead2go devices from Matrox to do what you're talking about.

Solution 2:

It is quite possible that the cables you saw were not plugging into a normal DVI port, but into a DMS-59 port (especially if you saw it on a Dell). DVI and DMS-59 look quite similar unless you look close enough, but the DMS-59 connector has in fact the equivalent of two full DVI connectors, and thus needs the split cable (you cannot directly plug a DVI cable into a DMS-59 port; it will not fit).

These ports are normally used so a smaller card can be used for two DVI or VGA monitors (Dell likes using half-height cards on some models).

Solution 3:

Your card has two Dual Link DVI connectors (see Wikipedia page here). However, a Dual Link DVI connector cannot output two independent displays -- it is used for driving higher-resolution monitors (2560 × 1600 as opposed to 1920 × 1200 on Single Link DVI).

Solution 4:

You cannot split a single DVI port to two monitors. I have seen splitters on video cards (like the Dell I am on now), but it's not connected to a DVI (though it looks roughly the same size), but another style of connector to two DVI's. I do recall seeing a splitter from a DVI to two DVI's but it wasn't used for two monitors but for a monitor which required two DVI inputs.