An update. I'm not proud of the fix but it's working. After trying everything and wasting a lot of time and effort I went into my bios and chose the "overclock by 5%" option. I don't like overclocking and never do it but this time it fixed my problem. I'm figuring that the DDR3 memory on the X1800XT was too fast for the system's DDR. Now the problem has gone away. One of the good things about 64 bit is that the cpu runs cooler because it processes data on a wider path and doesn't get so hot trying to keep up. I've noticed no rise in cpu or board temperatures so I'll leave it like it is for a while, until I find a better solution.
You folks on ARP forums have gone out of your way to offer suggestions and I appreciate it very much. I hope one day soon someone will need help in an area in which I'm proficient. Thanks to all my friends. Great forum.
