Try setting the jumper for 266Mhz bus and then clear the CMOS. Then try booting it up. That might help (and might not). I have heard some boards act flacky changing speeds and need a specific order to get it to boot correctly. Once they boot correctly, though the problem seems to go away. You might need to set it to 200Mhz bus first clear CMOS, load defaults, set it to 266... Try a few combinations. DO NOT RAISE THE BUS SPEED IN BIOS THEN CHANGE TO 266. This will overclock things quite a bit and will give you more problems. You need to get it running at 266Mhz bus and make sure it is stable befor playing with it more.
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