Thanks for the info, my sites are on 'bixel' and I rarely notice any speed problems. In-fact, as Mousee mentioned for his site, my sites seem be loading faster than ever since the recent extended outage.
It is possible that someone on your server is using more than their fair share of resources. I would suggest checking the server load (via the shell) during the slow periods and, if the server load is excessive, contact DreamHost support with the details and request that they put you on a server with less load.
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