Computer won't boot with new video card

Hello,

I have hp pavilion 500-277cb and I love it , but It wont work with my new video card

The video card is 
Sapphire ATI FirePro 2460 

I heard the 6 beeps , and I disabled secure boot and enabled legacy . It does not beep , but It does not boot either, just black screen. 

I seem the have the latest bios , and windows 8 

What else I can do ? 

Thank you so much 

Best,

Korhan