I am not 100% sure, but I think you will get 10% of the purchase price if your rewards are set to 'recurring'. However, if your rewards are set to 'one-time payment' I don't think you receive anything.
Here are a couple of quotes from the [url=http://www.dreamhost.com/rewards-terms.html]affiliate program terms[/b];
[color=#0000CC]"Recurring Payments will be applied to customer's account every time a payment is made by both referrals and sub-referrals."[/color]
[color=#0000CC]"One-time Payments will be applied to customer's account the first time a referred (or sub-referred) customer makes payment for any full hosting plan (including dedicated servers)."[/color]
To find out for sure, you should ask the question of DreamHost using the contact support function of the panel.
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