3 Monitors, 1 graphics card

I have a Nvidia GT 120 graphics card. It has a VGA, DVI and DMI output. Can I have 3 monitors with this? One for each port. Also if not, can I use DVI and HDMI and have 2 monitors. I know I can do 2 with the VGA and DVI but I am wondering about DVI and HDMI. Also my last question is, if I can have 2 monitors with the DVI and HDMI, can I use a HDMI to DVI cable and still have the same success?

I have a Nvidia GT 120 graphics card. It has a VGA, DVI and DMI output. Can I have 3 monitors with this? One for each port.

Out of the box, the NVidia GT 120 will support multiple monitors, as in two (2) monitors. This is typically achieved by routing one monitor through the DVI output and the other through the VGA output. You should be able to use the HDMI and DVI for the two monitor set up, but YMMV depending on how the HDMI is being routed in the card.

To use three (3) monitors, you'll need to purchase a second video card. However, you can could use a hardware appliance such as the Matrox TripleHead2Go with a single video card to achieve the three monitor setup:

Matrox TripleHead2Go is an external multi-display upgrade that adds up to three monitors to your notebook or desktop computer. Ideal for professionals requiring more desktop space for maximum productivity increases and gamers wanting a totally immersive experience, this small box lets you run different applications on each display or view one application across up to three monitors. Available in DisplayPort, Digital, or Analog Editions.

Finally, regardless of what type of set-up you choose, you should consider using an application such as UltraMon to manager your multiple monitor setup.

Edit 2010-05-20
Jeff Atwood of Coding Horror has recently posted a good article titled: Three Monitors For Every User.

You can definitely have two monitors, but most likely the DVI and HDMI share the same output (both are really similar digital formats).

The exact configuration depends somewhat on the OEM. What brand and model is the card?

Maybe this would help? http://www.nvidia.com/object/product_geforce_gt_120_us.html