PCI Express to External Memory Reference Design Qsys(Arria II GX): Data Verify Failed

Hi

I am trying to run the reference design with the guide of an433.pdf.

In the PCI Express Demo Application, When i select the run Onchip DMA Test or DDR DMA Test with the following setting:

- PC > FPGA

- Enable the check data

It always shows that data verify failed. Is there any possible reason will cause this?

Is the item below will cause the issue:

1. The pcie slot on PC motherboard is x16 and the pcie on arria ii dev kit is x8

2. Ignore the found new hardware wizard after the arria ii dev kit is plugged onto PC pcie slot

Thanks