do you mean the card is still in idle clock speeds? because thats normal, it wont go up to normal clock speeds until you do something that requires it, to save energy.
or
do you mean, pc falls asleep, you shake mouse to wake up rest of pc, but screen stays black? ect ei. graphics card not showing screen pic?
you need to explain your situation better than what your doing.
In short, the most likely cause of all your problems is somewhere to be found within your bios settings.ASUS appears in 14 out of the 16 pages in this thread!!! Not saying everybody having this problem has an ASUS motherboard but if they do, and it seems a high percentage of people do, then they need to disable the PLL Overvoltage in their BIOS!!
IT ACTUALLY WORKS! Not just a workaround, my Computer AND Monitor now both wake from sleep by simply moving the mouse!
quick solution? turn off sleep state, and turn off pc when not in use.
Things to check:
Motherboard Bios settings: <---------------
"Repost Video on S3 Resume" or such disabled. Could be the root of your problems.
Also common with asus motherboards (from a google thread, about issue):
In short, the most likely cause of all your problems is somewhere to be found within your bios settings.
** also this issue is quite common with windows7.... I believe theres a hotfix from mircosoft somewhere for it.