asus p8z68-v lx
intel i5-2500k
8gigs of ram
msi twin frozer nvidia 560ti
reused the power supply and video card from the old system.
psu is a thermaltake toughpower 750w (model w0117)
Under normal circumstances (email, netflix) it worked fine. But as soon as I started video games (skyrim, battlefield 3) it would hard reset. There have been several bios updates over the last year that I have applied. They only allowed me to game for about 10 before it would lock or hard reset.
Went through the normal steps. no errant voltages on the psu, no heat problems. if I replaced the video card with an amd 5770 it would also work fine. MSI certified the card as free of defects.
Solution:
after reading several articles about the new haswell cpu and the new power states it has, I began wondering if, due to the age of the psu, if there was a possible power state that it didn't support. After all its at least a 5 year old psu.
so I replaced the psu with a corsair tx750 haswell certified psu. So far I have played bf3 for 2 rounds, and rising storm for several hours last night with no issues.
with haswell upgrades happing, it's something we might see again, but definitely not a run of the mill issue.