W2000 slow browsing of network resources

Our mixed mode W2K enterprise network ocassionally
spawns a workstation that cannot browse quickly thru network resources. We have both types of workstations–fresh W2k Ghost images and NT4-to-W2k images that have this issue. Only a few machines show the problem, but it is a headache , nonetheless.Autodisconnect is disabled without improvement in performance. There may have been a discussion once that mentioned this subject as an inherent problem in W2K , but I have no recollection of the cause-cure. Can anyone offer up advice ?