PSU for new build

[nbus]

Just placing final orders for new system - as specced in My System

Final bits are case and PSU

The PSU is what I'm concerned about at the moment.
Some cases include one (e.g. AntecSonata has a decent 500W PSU)
But the MoBo uses a 24pin ATX2 socket.
I think that the antec PSU has a 20 pin plug

This won't go together will it?
So the best bet would be a case with no PSU and then a separate PSU.
Is that right ?

These feel like dumb newbie questions (which I'm not really) but I'm trying to stick to my budget but I also don't want to end up with a rubbish PSU - I know how important this is.

That was why I like the Antec cases, because they have good PSUs.
Just not sure if they'll work with the MoBo (Asus P5KC, iP35, S 775)

I'm planning on air cooled o/c later too

Any ideas/advice

TIA !
Nick

[Voodoo54]

Corsair 620 Watt

[Blitzen]

Corsair 620 Watt

Overkill.
HX520 is plenty.

[vicar]

Try corsair's maker = Seasonic

[DratUK]

As Blitzen 520 HX Corsair