Yeah - I had the same blue-screen problem. As mentioned above, the solution is documented on the xilinx website - download the new driver files and it all works ok. However, be aware that if you are using win2k, the same thing will happen again (do they ever learn?) if you install version 5.1 - once again, download and install the 5.1 fix from the xilinx site before you reboot your machine. Otherwise it's blue screen time, and I actually had to format my drive and reinstall the operating system, as safe-mode wouldn't boot...