|I assume you mean a 460w psu, not 260w. Regardless, let's forget about watts for awhile. We need to know the amps available on the +12v rail(s). A rail is the same as a circuit.|
Modern psu's can have a single +12v rail or more than one...2, 3, or 4 are common now days. Whatever you have, each will have an amperage rating. If you have only one +12v rail, it must have 24a or more. If two, each should have something like 15-17 amps. All this info is on the label of the psu. That's the information we're asking for.
The psu might not be the problem but we need to get it out of the way; easiest way is to give us all the info on that label.
Popular belief is that if you buy a name brand case, a name brand psu is included. That's not true; should be, but it ain't.
According to CM site, the 460w psu is included with a Centurion 534 and a 390w psu with the Centurion 5.
Check the label for us and we'll go from there; jam is on to the most common cause of your problem.