In that case you want to absolutely verify that the card will do what you want it to. If the machine is a big-name label, then there's a not-unreasonable chance that the graphics card is custom in design, so for example it's possible to find "Intel HD Graphics" implementations that do not confirm to the standard specs.
Also, given that the computer is a Small Form Factor design including a likely weenie-sized PSU, it's even more plausible that the graphics card may not be exactly what you might expect from the de facto standard for the GPU in question.
Squinting at that image, it looks to me like one DVI port and two HDMI ports. Based on that I think it's not unreasonable to guess that it will support multiple monitors. Whether it will do three though is a guess too far IMO.