[CentOS] centos 6 boot and install on hp dl380 G4

Hello List,

i downloaded centos6 x86_64. With DVD-iso1 i made a booteable usb-stick
(universal usb installer 1.8.5.7).
When i boot my HP ProLiant DL380 G4 from the stick, the CentOS boot
screen comes up and and the message
"Automatic boot in xx seconds..." appears.
* When i do not hit any key, the seconds are counted to zero an then it
starts again at 10 seconds - again and again.
* When hitting return, a boot menu appears:
 1) Boot
 2) Boot (text mode)
 3) Network Installation
 4) Memory-Test
 5) Boot from local drive
Only Options "Memory-Test" and "Boot from local drive" work.
When choosing Option 1,2,3 i'm always pushed back to the menu.

How to install CentOS vom the stick? Please help me to find my  mistake.
Please tell me, if i can provide any information.

Bye,
Florian