The manual doesn't say how many monitors it supports (at least, not that I can see), but in theory an APU can support the use of both outputs.
The DVI-D appears to be only single link (max: 1920 x 1200 @ 60 Hz) and the HDMI is 1.4, which can only do 4K at 30 Hz.
Are you having trouble getting the second monitor to work?