Ok, here's one I just stumbled across the fix on.  Ever since I install Solaris in a Virtual PC environment I haven't been able to get video.  It appeared it was a sync problem, but my experience hope it was something as simple as a color depth problem and that's what all the research pointed to.  The resolution was actually simple and it was due to the way the Solaris 10 manages X11 now. 

Problem:  Video appears double scanned when running Solaris 10 in a Virtual PC 2007 environment.

Fix: Usually from the windows you can see well enough to start a command line boot.  Boot into a command line interface and perform the following procedure to change video color depth to 8 instead of 24 which Virtual PC does not support:

# svccfg <ENTER>
svc:> select application/x11/x11-server <ENTER>
svc:/application/x11/x11-server> listprop options/default_depth <ENTER>
options/default_depth integer 24
 
svc:/application/x11/x11-server> setprop options/default_depth = 8 <ENTER>
svc:/application/x11/x11-server> listprop options/default_depth <ENTER>
options/default_depth integer 8
 
svc:/application/x11/x11-server> end <ENTER>
#

CREDIT: I want to give all credit to the site I found this on which of course was http://docs.sun.com and of course to Sun Microsystems.  Thanks guys, great information.