H87m Pro4 - is PCIe x4 slot graphics only?

[nplack]

As stated in the title, is the x4 PCIe slot on the H87m PRO4 for graphics only? I need this slot for a nice wifi card and I know some boards do not allow anything but graphics in the second slot. Manual only states that the PCIe x4 is for graphics, and never mentions expansion cards. Trying to figure this out before I build a system around it. Thanks!