As far as the error information posted it doesn't provide enough details to show what the actual problem is. I've had some real fun debugging video and sound drivers alike in XP on the new build here where the event viewer shows that something happened and when but not that the system rebooted suddenly when a sound in game starting looping itself and then the XP crash control took over.
Try turning on the system and seeing nothing where the desktop should be after installing a new patch for the latest ATI catalyst. That's supposed to correct problems being seen while gaming yet seems to be a cause for new ones?!
The TP3 650w model will be a boost for the system there with the SLI setup in order to provide adequate power. Without SLI or Crossfire plans here I ended up going for an OCZ GameXStream instead of the Corsair HX620 someone was pointing me at when discussing supplies. The Corsair models have an energy saving feature while the OCZ takes a pounding and remains stable.
And you are quite correct on seeing a high price for the TPQ line now offered by Antec. They are finally seeing some gaming type supplies coming out but keep a slightly higher prices. That's one reason for going for the OCZ model over the Corsair when looking over the cost totals here. The 650W version of the TP3 line will be better then their 550w version since you are planning some ocing there. The model will offer a few more amps on the rails being a lower end Seasonic made supply.