lol bfg a good psu? no.... who ever told u that psu was good for overclocking was wrong, from the graphs u posted like this one:
the blue line is where ur supposed to be, the red is where u are, ur getting like 10.5v out of something that is supposed to be giving 12v a good psu will be like .1 or .2 off maybe, a bad psu will be like .5 off. ur 1.5 off if occt is correct, look in ur bios under like monitoring or tempatures or somthing im not sure every bios is different but look for it(someone w/ a biostar i45 help me here). but i personally think just by looking at ur stuff that its ur psu that is causing insability
edit: here is a graph to compair to, i just ran occt for 3 min and here was my 12v rail:
keep in mind i know my windowns reading is a little off it reads about .08 lower then bios reading.