Just a quick heads up, pRIMEGRID have released a new unit type - this is probably completely the wrong term!
http://www.primegrid.com/forum_thread.php?id=5557
Just a word of advice. In that thread it above does warn that the new units run hotter and to make sure that your machine will run ok.
When I ran some units last night my core temps jumped at least 7°C almost instantly

You maybe want to keep an eye on your machines to see if you are happy with the way they run.
(edited thread title to be more helpfull)