didnt read the other posts, but: its totaly safe to use! You wont be able to bring this PSU to its limit with these hardware under normal conditions.
Myself, i was running an HD5850 with 1,17V and 950Mhz, the load of the full pc (inkl E6300@3,2ghz and 4gb ram etc) was about 180W.
Iam using a 400W PSU, so i would be able to fire 2x HD5850 even with oc with this psu.
Dont be scared, this psu will easy handle a single HD6950 with moderat oc (in my opinion even very high oc).