Poser is looking for other copies of itself on a local area network, not the internet. If you set your firewall to allow it, perhaps it will stop the multiple attempts. I don't think those network queries would cause your machine to go into overdrive though--sounds more like CPU/disk activity. Poser isn't a "cheap date" sometimes :-)

"Democracy is a pathetic belief in the collective wisdom of individual ignorance." - H. L. Mencken