There are apparently many reasons for freezes in Windows 8.
I list here some of the known fixes, including that of Hyper-V below.
- Disable dynamic ticks by doing in CMD as administrator (no known reason why it works) :
bcdedit /set disabledynamictick yes - Disable C-states or C-modes if your bios allows it
- Activate Hot Swap if your bios allows it by setting it to Enabled
- Update all drivers, if possible from the manufacturer's website
- Fully patch Windows, including optional updates
- Activate Hyper-V (some people report that disabling dynamic ticks solves the same problem)
As regarding Hyper-V, I quote from Windows 8 Web Browsing Freeze :
By enabling Hyper-V on your machine, your root OS (which you use) will now run on top of a Hypervisor, which means it's essentially visualised. It's not in the same sense as a virtual machine, as your OS will still have direct hardware access to essentials such as graphics cards for gaming.
If you already run a virtualisation environment such as VMWare or VirtualBox (with 64-bit VMs only), they will no longer work. The reason is that the Hypervisor doesn't expose the VT-x extension to it's virtual machines (including your new root), and so other virtualisation products can't be ran with full effectiveness. The obvious workaround to this problem is to convert your VMWare/VirtualBox VMs to Hyper-V, and import them using the Hyper-V Manager.