When using an adapter or not straight connection, the resolution will be limited by the cable.
The following are the resolution supported by the HD4600, however it is going to depends on the type of processor and the output you are using.
DisplayPort* 1.2 / eDP*
H-Processors: 3840 x 2160 @ 60 Hz (Ultra-HD)
U-Processors: 3200 x 2000 @ 60 Hz, 3840 x 2160 @ 30 Hz
Y-Processors: 2560 x 1600 @ 60 Hz
HDMI*: 4096 x 2304, 3840 x 2160 @ 24 Hz / 24bpp
DVI: 1920 x 1200 @ 60 Hz
It is important to also have all the latest graphics drivers and BIOS installed on the system. I would recommend you to check if you are using driver version 3960 which is the latest generic graphics driver available.
Intel® Iris™ and HD Graphics Driver for Windows* 7/8/8.1 64bit
Intel® Iris™ and HD Graphics Driver for Windows* 7/8/8.1 32bit
Bear in mind that we provided generic drivers; therefore sometimes these cannot be installed on HP systems or the installation of them could overwrite HP customizations and possibly change the functionality of the graphics, but you can give it try.
Thanks for that information Sylvia_Intel! I will give the graphics drivers a shot. Based on the information above the DVI cable is limited to 1920 x 1200 @ 60 Hz so it may be a cable issue? I don't have an HDMI port on this CPU. Do I have other options as far as the cable goes or do I need to look at updating my hardware? I just don't want to run the new drivers if it is a hardware issue. If you think running the drivers will help I will definitely give it a shot!
The driver update will not make changes on your system in order to get 4K resolution.
It will fix some graphics issues. You can check the following URL for the complete information http://downloadmirror.intel.com/24348/eng/ReleaseNotes_GFX_15%2036%207%2064%203960.pdf
To get 4k resolution it will be necessary to upgrade your board to one that has HDMI port.