Victorvideomaker had the same issue and had to set which GPU to use and performance or battery saving: http://forums.pinnaclesys.com/forums/post/804883.aspx 

In my Opinion, either windows or your bios is not letting PS18 use the Intel integrated graphics GPU, only the NVidia GPU.  You would be better using Intel GPU for PS18, it was much faster. See if you can follow the link below and set PS18 to use the Intel GPU rather than the NVidia GPU.  If Intel GPU doesn't show up in the list, then ...

Euphonograph:Any ideas, thanks, have a great weekend  Is this 18.1 or 18.5? Is it at least working now? If you need dolby 5.1, sounds like you're going to have to learn to live with it. 6 minutes to render a 60 minute clip isn't bad for a program that is six years old.

Those sound like average or peak frame rates, not constant.  If you don't trim the clip, some of the time it will work.  If you trim it and get the black frames or grey screen with circle arrow frames, sometimes you can just move the in or out point(frame) 1 or 2 frames either direction and it will work again.

You can use Mediainfo then click on view/tree and then scroll down to video to check the file framerate .  A lot of security cameras and cell phones use it to save file space, but it is next to impossible to edit on a timeline because the timeline has to be a fixed frame rate to do non-linear editing.

Is it constant frame rate or variable frame rate?  If it is variable frame rate, try running it through handbrake and converting it to constant frame rate, then load it into PS.

What is the camera and what is the file format?

Have you looked to see if there is a bios update?  Seems like there might be a conflict between the intel cpu/gpu graphics and the nvidia gpu.   Strange that intel acceleration doesn't work properly.  I've never had it fail.  When I bought my amd graphics card and installed it on my pc where I was using just the onboard ...

I sure do.

The title of the post is painfully slow rendering on New laptop.  The op post before mine was that he tried the studio drivers with no luck.  No luck, with the title of the post, means it wasn't faster.  The studio driver will not increase the performance of ps, only hamper it.   A month or so ago there was an nvidia driver ...