Generally "double what you're using", the cache can grow quite quickly. With my forums I make sure I have at least 300MB freespace; if your board is taking up 100MB I'd reccommend double if not tripple free space for growth and caching.

I would never reccommend turning off the cache or blocking spidering; web spidering will bring a lot more users to any forum, caching will speed up any forum as well.

And Ian, if he wants my choice of ISP he can always read my signature.

I am a Web Development Contractor, I do not work for UBBCentral. I have provided free User to User Support since the beginning of these support forums.
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