How to fix video card compatibility issue?

Just bought a Radeon hd 5450 graphics card and after doing some research I figured out that despite the fact that they say pci express is backwards compatible, this graphics card which is pci-e 2.1 doesn't work in the intel 915 series pci-e 1.0, which is my motherboard (D915GAV to be exact). Is there anything I can do to fix this problem? p.s. I have already tried updating my BIOS and that does nothing.