I have installed several Xecuter 3 chips, on all versions except 1.6. Ths was my first attempt. Everything seemed fine, but once I threw it all together it fragged. I disabled the chip, and it boots to m$ dash, and gives me the error 6, which is no big deal. I boot to the backup BIOS, and it will boot to that. I just pulled the X3 from a system that was working fine, so I know the BIOS on it is ok. The BIOS is the X3 1959. I think it is a v1.6, and not 1.6b. It has the Xcalibur video encoder.If anyone has any ideas, please let me know. Thanks.