The other comp is an pretty new Acer laptop with WinXP and an RME Multiface. The problems are not as bad as with the Dell, but, especially when a lot is happening in the gui, i regulary get clicks, while in 0.37 i only got clicks when using readsf~ until now..
well, i'd personally suggest, you try to use the developer branch ... there are binaries for windoze on the sourceforge page ... using the cb_scheduler option, you should be able to achieve pretty low latencies ...
cheers ... tim