Hiya Rip,
Well the theory is this (ps: i send all games in x64 to a folder on C: i call Games)
Whenever i format and install vista i turn UAC off to make life a bit simpler
Now i came across a post about elevations not happening correctly due to UAC being off where some drivers etc are involved
So i put on UAC without rebooting and removed nvidia driver
Rebooted and redid nvidia driver, answering the UAC prompt
Now just before doing the UAC back on i also did something in the nvidia and System32\Drivers (i had forgot, as i'm trying that many ideas out lol)
So now i have edited a certain file to do with the driver, Turned UAC back on, Redone drivers and all is well
This is on vista ultimate x64 running both AA's @ x4 and other options in driver options i have on
Plain SH4 1.5 using torpedo school
No lockups like i had, So now i've gotta rollback and see if it's solely UAC (you seem to confirm it might not matter whether it's on or off, so this theory maybe wrong) that's the problem if it's off
Or is it what i've done to edit the driver file (tried so many drivers i installed 1st i clicked on and they were 158.24 !!!)
Will get back asap i try combinations
No doubt what i've typed makes no sense as i'm dog tired but hope you catch my drift
Ciao
Def