I had this problem in W7 Ultimate 64bit but when I updated my Nvidia drivers to the latest ones the problem went and it is now back to 60hz all of the time.
It selects it ok. but it's when u go back to it, it stays at 59.
updated the drivers. still no joy.
so i got a program called power strip.
Can use 60hz now. Works a treat now
but have to keep choosing 60hz each time you play a game you wont to run at 60.
Thing is, on some games like pro evo 10, on 59 hertz it stutters.
on 60hz it's smooth.
hence why i need 60herts. i know others dont think it matters. but in some cases it really does.
I'm waiting for 64bit to come now,(as i lent 32bit to see how it run) as im using 32 bit with 6g, but shows i got less.
So maybe it will sort it out, as i can't have the best of both worlds. as when i play Assassins creed with directx 10, it wont stay in full screen mode.
only when i delete powerstrip it stays full screen.
alt-and return goes into full screen for 2 seconds, and then goes right back to windows mode again.
But that's another story.
Cheers.
not going into detail, no point now.
but thanks for the link.