I have been suffering with this problem for months now and it finally got to a point where I would routinely crash about 30 minutes into browsing. I had tried every proposed fix presented in this forum with no success.
The problem reached a head only a few weeks ago, after updating all my motherboard drivers. I was overhauling my system after neglecting it for a few months.

I thought I had tried everything in terms of removing all my drivers and replacing them with alternates from Microsoft, the manufacturer of the device/chipset, and my motherboard maker. Finally, I opened a call with Microsoft.
They had me perform a whole bunch of actions, including resetting the IP stack and performing an in-place upgrade of windows. By this time, I was very cautious of making only one change at a time, writing it down, and then trying to play a movie to see if the browser (and then computer) would freeze. Sadly, none of their steps worked. The last step (and the final step in Microsoft's troubleshooting methodology, by the way) was to erase everything and re-install Windows from scratch.
Again, I was cautious to install one driver at a time and test movie playing. To my surprise, I started to run into trouble after I installed the onboard NIC driver but the trouble was not the same. It could have been a fluke with my Internet connection. After the next step, however, the problem returned as it was originally. This was after installing the driver provided by my motherboard manufacturer for the SATA RAID controller. (I am using RAIDed configuration.)
The problem was the Intel Rapid Storage Technology driver!
Unfortunately, I was using the latest version of the driver provided by Gigabyte. My only option would be to downgrade but the driver is non-downgradeable! I decided to look for the driver on Intel's site. Intel provided a more recent version of the driver. Once I installed it, all my problems went away!
I am currently using all the current drivers from my motherboard manufacturer, except for the onboard SATA RAID driver, which was downloaded directly from Intel, and everything works great.
For those who would like to know. I have a Gigabyte GA-X58A-UD3R (Rev 1.0) motherboard. I will be looking to post this thread on Gigabyte's forums as well.
Thanks for all your help and good luck!