XPS 15 L502X - Flash Video Problem

Hey guy's, i am having a problem with my dell xps 15 L502X, it is the model with the i5 2450m cpu and the gtx525m gpu. The problem i am facing is when i try playing flash video in a high resolution i.e. 720p or 1080p i get stuttery audio and video, also most like my low powered netbook. I have installed all the latest drivers including chipset, audio, and video, both integrated and the nvidia chip. Yet I am still getting the problem. The weird thing is when i play video locally i.e. a dvd or and avi/mkv the video and audio are fine and those or big 1080p files.

When i first researched the problem i came across nvidia optimus and that it may be causing problem, i now understand exactly what nvidia optimus is and have tried a few things to problem solve the issue. Also the dell website makes no reference to nvidia optimus, which i find odd, frustrating and confusing, a bit like their drivers page and lack of recovery images to avoid all this driver shenanigans!.

The first thing i tried was running both the browsers ie, chrome and ff with the nvidia gpu and then the default integrated gpu, restored it both times after making the changes the the same issue on all browsers. So then i started thinking, maybe i have installed a wrong driver somewhere and its causing the problem, checked all the drivers in device manager they seem ok (though how would i check if i installed the wrong integrated graphics driver for example or chipset driver - i am running windows 7 home premium 64bit).

The other route i began looking down after presuming the drivers were all ok was flash itself, though i have read things and problems it has caused in the past and tried solutions peopled offered i have reversed them as none of the solutions worked.

Another thing i would mention is would the battery be causing this issue? as i need to replace the battery bit i don't see how it could cause such an issue. Another issue is heat, could heat cause an issue like this? (about to turn on my laptop and play a 1080p video and see if it play that way i can narrow it down to not being a heat issue as the laptop has been switched off for over a week now...)

UPDATE: Heat is not the issue, just tested it.

Also if there's anyone out there how could share a copy of the dell xps l502x i5 gtx525m recovery image with my i would be very greatfull (dell should really have a download facility for all of its customers in this day and age.).

So has anyone got any suggestions because i am sure as hell stumped. Also i would like to note that i have an honours degree in computer science and 10 years computing experience under my belt, i would consider my self technical to the point where i have contemplated stripping the laptop down removing the heatsink and cleaning it of dust and applying the gpu heat paste. So any solution no matter how complex i am willing to try.