All five games will be nationally broadcast. UCB-WSU and ASU-OSU will be on FCS Pacific and their local FSN affiliates, which is national if you have the right cable package. Arizona-USC, UW-Utah and UCLA-Stanford should all be on FSN/Comcast throughout the whole country.
The SEC sells tier one rights to CBS for one game a week which usually ends up on the main channel. Tier two rights go to ESPN, which obviously doesn't have a regional set up a'la FSN. Tier three rights are left up to the schools, which usually go to local broadcast or PPV.
Pac-12 sells tier one rights to ESPN with some special caveats for FSN, like this week. Tier two and three also go to FSN/Comcast with no rights to ESPN, which would explain why you never see Pac-12 games on ESPN3/GamePlan -- because the only games that ESPN gets are nationally broadcast on ABC/ESPN/ESPN2, while the type of stuff that would wind up on GamePlan is sold to FSN.