T-bird + KT7-RAID not able to use .5 multipliers??

[AMDfreak]

OK guys, need your help here. Got a KT7-RAID board flashed with the UL BIOS and a T-bird 800. Used the pencil trick on the L1 bridges and the whole multipliers work fine(8.0, 9.0, 10.0) but not the 8.5, 9.5, etc. When I try to boot at 8.5x100 it posts at 800, 9.5x100 posts at 900 and so on. Am I missing something?