[BluffTHIS!]

Even running a 32 bit OS shouldn't be a problem, since it should only merely be unable to take full advantage of the processor. A lot of party problems seem to be related to memory usage on older systems, so I would tend to think this is a video card or memory problem, although since the client application presumably acts through the OS to address memory this *shouldn't* be a problem (XP has much better memory managemet than 98/ME for example). If the app directly accesses memory then there might be a problem although you would have to get someone more familiar with 64 bit systems to tell you what. You probably should call their customer service though regading the problem. You need to be insistent and ask to speak to a tech rep and not the normal reps who put you on hold while they ask the tech reps. I have been able in the past to get to a tech rep and they are very knowledgeable in *most* cases. However there is also a good chance that they don't yet have any experience themselves running their client on 64 bit systems, since many of us are waiting until the OS and major apps are tailored to take full advantage of 64 bit processors to get a 64 bit system.