Finally we've been able to PXE boot multiple images, which is absolutely a life saver verse USBs and CDs. We've successfully been able to do this on all sorts of HP devices except our new batch we bought of HP Compaq Pro 6300 SFF's.
When we boot into PXE, we select maintenance from the menu. From there, it will flash and adjust the resolution of the blue "ZenWorks Imaging" splash. It will then turn black. I go to ALT+F2/3 to see what it hangs or stops on and nothings there because the screen turns black immediately.
The NIC is a Intel 82579LM Gigabit Network card on the standard HP motherboard. I've looked into this and the NIC drivers were added a long time ago to ZEN 10 or 11? I believe.
For reference, this is the same as what I'm experiencing:
Support | PXE boots to black screen on select HP devices
It is worth noting that booting via USB or CD/DVD will bypass this issue.
Any help would be great though; thanks