Its a desktop.
I keep it on pretty much all the time because I get on and off the comp all the time.
My mistake. I just affiliate optimus and alienware with laptops.
In that case, 24/7 shouldn't be an issue. If you are really concerned about power management, you may want to look into under-volting as well. It can yield quantifiable power savings if either the GPU or CPU are under-volted. Manufacturers tend to run the voltage a few mV high to get a few more chips stable, but most don't need the extra voltage.
My other points still stand though. GPU driver update should be helpful, if anything, and restarting Windows is good every once in a while.