I think its about the Intel NIC, SoundCard, SandyBridge CPU or nVidia Card.
My two other test machines does not have any lockups, they use i7 875k or phenom 2 1100t, Realtek Nic, Realtek Onboard Sound, AMD Radeon HD7970 or HD6950 and Corsair Force GT 120 SSD
Id like to hear what NIC, Sound, CPU and GPU combo everyone uses and report if they have lockups, just because some people say its GPU problem and some say its Windows 8 ethernet drivers or then like andressergio said it could be audio drivers also.
Edit :
Found some more possible causes, they think its C-State problem affecting only Intel CPU's and certain chipsets .
http://www.eightforums.com/crashes-d...ze-post-4.html