Help - Combining PDF's is painstakingly slow!

I have PDFCreator installed on two Windows machines running XP SP3.  Both machines have similar tech specs (processor, memory, etc.).  One machine combines multiple (6+) PDF's relatively quickly; the other machine is painstakingly slow.  I have uninstalled / reinstalled on both machines and am running the latest build.  Does anyone out there in PDFCreator land have any suggestions as to how to bring the slower machine up to speed?  Thanks in advance!