said by FizzyMyNizzy:Yeah throughout some research I found theres a setting within the nVidia driver setting control panel that lets you turn off this 'power saving management' and always be at its full clock speed. It just caught me off guard when I installed all my new hardware and was getting random crashes.
Your gtx 660 ti is fine. When you are not playing games, or watching movies. It will lower it clock speed. Most people call it 2D clock speed. When you play games or watch video it will go back to 900+ mhz speed 3D clock speed. I do notice nvidia is having an issue with boost speed. Some times in game you will be on boost speed. A bit later boost is turn off for no reason. Tho, this bug doesnt happen when you benchmark using 3dmark 11, heaven etc.
IF you are playing a game and it is stuck on 2D speed than you might want to check the bios, check the installation, maybe try the newest beta driver etc.