Trying to run OS X from an External

[Panda]

Hi guys i'm here for help again cause i seem to be stuck heres where im at i successfully installed Kalyway Leopard 10.5.1 SSE2 SSE3 on the external HD but when i try to boot from the external nothing happens i get a blank screen i know it was a successful install and i know my PC can run it

heres my specs:
HP Pavilion dv6875se Special Edition - Core 2 Duo
* Processor Intel Core 2 Duo T5550 / 1.83 GHz
* 64-bit processor
* Data bus speed 667 MHz
* RAM 4 GB
* Hard Drive 320 GB - Serial ATA-150 - 5400 rpm
* Type DVD RW (R DL) / DVD-RAM
* NVIDIA GeForce 8400M GS
* Video Memory 256 MB
* Audio Output Features Altec Lansing speakers

i had another post here with another issue with i fixed thanks to Hara Taiki and Dies heres what we worked on

i messed with my Bios to fix my previous issue but now i don't get shit, just a blank screen any ideas? also when i just let windows boot and try to go into the external to reinstall i can't see it anymore from windows i can only see it through the Bios so i know its working just can't see in it windows