First post, by smtkr
Today, I tried to swap out my old Celeron for a Pentium III 800EB. I have an Abit BX6r2 for this project. I installed the CPU, booted up, and configured the CPU in the Soft Menu interface as 133MHz FSB and a 2/3 AGP multiplier. The system posts, but it has a black screen when it gets the part where it's supposed to load Windows.
My first instinct was that the graphics card can't handle the 88.7MHz AGP bus. I think I have ruled this out. To test this, I configured the system two different ways: First, I configured the system for FSB=83MHz with a 1/1 AGP multiplier. That booted into Windows fine and ran through a suite of benchmarks without any stability issues. Second, I configured it at FSB=100MHz with a 1/1 AGP multiplier and the system was able to run through various benchmarks just fine.
This testing seems to indicate that the video card can tolerate AGP bus speeds from 66MHz through 100MHz.
I also configured the CPU for 124MHz x 6 = 744MHz with a 2/3 AGP multiplier. That works fine and runs through my benchmarks too (albeit, northbridge and power mosfets are starting to get noticably warm at this speed).
The last thing I tried was relaxing memory timings. That made no difference.
Are there any other things I can try before I start swapping through my CPU collection?