Running slowly

I was reading the benchmarks for this and I am having some issues with them. It is probably just my Ogre install, but here is what is happening. I use a Radeon HD 5770 1GB video card in my computer which is better than the 7800GTX that the benchmarks had been claimed to run on. I am getting about 30-40fps at 1920x1080 with Example 10 and the benchmark said 100-150 FPS with the 7800GTX and 240,000 trees. I use Ogre 1.7.1 32 bit and the DX9 renderer since neither the DX10 or DX11 ones are working for me.