Update -
I ran an odd test from Intel called BITS, and it showed an error in the MP Table and two errors in MSR. Don't know what that means, except that "MSR" shows in the "havdetectiontool" results I posted above.
Also, I strictly followed AGAIN the instructions above in the havdetectiontool test -
1) changed the BIOS to DISABLE the two virtualization options, did a complete power down, waited, pulled out AC plug, waited, pushed power button to discharge the capacitor, waited, connected the AC cord, waited, powered up, ran the havdetectiontool test, got the same results.
2) changed the BIOS to ENABLE the two virtualization features AND the Trusted Execution feature, did all the same power down and back up recycling and got an immediate boot error: "Alert! Invalid Trusted Execution Technology Configuration. Please refer to the Trusted Execution Technology Setup option helptext for details." But I have no idea where that helptext is. In any case, it is EXPECTED that Trusted Execution not work. But surprised it prevented boot-up.
3) Went back into BIOS, turned OFF Trusted Execution, left ON the other two virtualization options (so I'm back where I started), did the whole power off wait AC out power on again, booted OK, but same “Hardware-assisted virtualization is not enabled on this computer” message from the MS havdetectiontool test - back where I started.
Big pain in place where I sit on Michael Dell's nose.
Are you awake after reading this exciting saga? Any ideas?