Windows 7 - aero slow motion

Hi,

I've been using Windows 7 ultimate x64 since release day and it has always ran great. However, every now and then when i boot into windows the slow motion aero effect keeps being activated automatically, but when i restart, aero goes back to normal.

It has never bothered me since it doesn't happen all the time. I was just wondering if this is a bug or can something interfere and cause it to be enabled?

I am using an ati 5850 graphics card with the 10.11 drivers.

Any help is appreciated, thanks.

Same has happened to me. I've never tried to enable the slow motion effect, and before figuring out it was an aero feature, I thought there was something wrong with my computer.
It happened about a week ago for the first time, and just this morning for the 2nd, however after rebooting everything was back to normal.

And thus I'd like to know why this happens, just like the topic starter.