From what I have seen from this issue it looks to be the Win32 & IIS based servers that have the most problems. I haven't come across a UBB 6 running on a *nix box which has hogged all the CPU load. I spoke to a couple of ISP's here in the UK earlier about this, and they said that they haven't had any of the CPU load problems with users running high usage UBB v6's.
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