I have to admit that I've never run an Invision Power Board, but since it seems to run under both PHP 4.3+ and PHP 5.0+ and MySQL 4.0+ and MySQL 5.0+, it is compatible with DreamHost's PHP and MySQL setups. There are obviously some specific aspects of the PHP setup that could still be hurdles.
DreamHost ended the hard 1hr CPU time limit but still monitors CPU and will contact you if your scripts seem to use too much CPU. They will work with you to reduce the CPU utilization of your processes before taking any drastic action or forcing you to the dedicated server option.
We're only DreamHost customers here, not employees. I like the L1 plan which I think is a fantastic value but my needs are modest. Others like the L3 plan because it has 3 phone support callbacks.
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