Frames issues.

Hi,
Can somebody please suggest an answer to my problem.
Basically its my frames issues in Skyrim. I don't know what it is about Skyrim but whenever I turn a corner or even move somewhere, my fps drop quite a lot, only to rise again, but then drop a second later. The game is playable but its really frustrating when nothing intense is happening and my frames per second are all over the place. I'm convinced it has something to do with the textures because when I'm standing still or walking slowly in some places, my fps hits 60. This is quite rare however and more often than not, I'm in the 30-50 bracket. But I'll be walking around at 50 fps and turn a corner and straight down to 30 fps. It causes considerable lag and it must somehow be avoided. I play with AA off and AF off too. I play on High settings but with some tweaks.
What confuses me is that games such as Mass Effect 3 the Demo all play very smoothly, all be it and 30fps, but at least it always stays at 30fps and never goes below it. Same with Dead Space 2, a constant 30fps. Both games maxed out. And Dead space 1, a constant 60fps with no drops at all (maxed out).
I've tried a few things such as trying out some mods but they don't seem to make a difference. The problem even occurs at lower resolutions.
Please help!

Dell XPS 17- i72630qm @2.0gHz - Nvidia Geforce GT 555M 3GB - 1920x1080 17" LED Screen

Thanks in advance
(title should be Frame issues)

Any help?

Thanks for the reply.
I always play at 1920x1080, I'll try at lower resolutions but that didn't seem to help last time I tried.
My Nvidia drivers are the 269.59 drivers, I know this isn't the latest release but I had to rollback, because with the 285.62 drivers, I couldn't use certain programs annoyingly. But when I was using 285.62, it didn't make any difference to my gameplay experience.
My Skyrim Patch is 1.4.21.0.4 which I think is the latest.
And my GPU temperatures are usually good, never go above 60 degrees and usually hangs around 55 degrees.
Vheers

I updated the drivers and the problems still occur but I lowered the resolution to 1600x900. So far, the problem has lessened and its always in the 40-60 bracket which is great. But there are still some places where the frame rate drops, but I guess it can't be perfect.
Do you think its worth using the beta drivers, because the 290.53 drivers have a lot of optimizations for Skyrim. Also, if I download the 295.51 drivers, does it incorporate everything from the 290.53 set? Or should I install install them one at a time?
Thanks

Okay great thanks. I'll install them and see what happens.

awesome, now go kill some falmer