Thanks GBowman, I put in the msiEnabled and it seems to be making a difference, although it's still not fully working. I added msiEnabled to all the passthrough devices, which includes the onboard USB, the Radeon 5450, and the Radeon Audio device.
What's happening now is that the GPU in the guest boots, the first time as before. When I reboot the guest, now the host doesn't crash, but the guest gets a blank screen and no screen shows up. Both the VI client console and the direct HDMI output from the VMDP GPU.
I'm gonna try to and tinker with the different combinations of the pcienabled, putting it on different passthru devices and see if that makes a difference.
Maybe it's my particular video card, a PCIE x1 HIS Radeon HD 5450. we'll see.
Pretty cool that you got CF working. My motherboard only has 1 PCIE x16 slot so I can't do CF. My goal is to get dual GPU's working, a fairly fast GPU in my x16 slot for playing games, then a slower GPU in the x1 slot for everyday stuff.
Thanks