Problem im seeing is that the corsair is not on the ati/amd certified psu list for that card (http://ati.amd.com/certifiedpsu), should i take this into account or ignore it?

Also if the hiper 580w (the first psu which i have now) is dual rail (which i think it is), then thus far i havnt had any problems with dual railing.

What IS dual or quad railing anyways...

Dual railing is where there are more than one 12V outputs from a power supply, most typically from modular ones where you can remove cables. Basically, it splits the power going into the PC into different circuits, so a 580W supply may actually behave more like 2 290W supplies, and hence why you can overload the things.

So it has more than one of the same cable coming out the back that goes to make the main wire loom? Yeah my current psu has one of those, should be no problem...

It does, but if you load one of the cables more than the other the design pretty much means that the PSU will suffer, despite being inside the advertised power margins.

Each of the wire bundles will have a rated power of its own, you can pretty much guarantee that one side will NOT take 580W, even if the other side's got no load at all.

Fair enough, ill load em as evenly as possible

In any case thats only for peripherals (dvds, satas, other cards fans etc), the gpu and mobo (consequently) cpu have seperate cables on my 580w hiper im pretty sure these ones will be the same

Dont even bother with ATi certified crap, nobody else does except the companies that are sad enough to papy to have their placed there, in theory if 1 rails is 300 the other 280 and the rail that powers the card say it needs 350 may be underpwoered or something that is my grasp of it but i dont bother with psu stuff