Atx Psu Cable Question

[the lone gunman]

ok im buying a lian-li pc-v1000 case but i think my PSU power cable may be to short to reach the mobo so i have bought an ATX 20 pin exstender, however my mobo asus k8v-x se AMD s754 also takes a 4 pin from my PSU. my question is: what is this 4 pin cable called? as i need to buy an exstender for this too

 

[[Spectre]]

P4/AUX connector.