The Sydney Morning Herald reports that Westpac's online banking operations slowed to a crawl yesterday.The reports quotes a bank source saying the system dropped to 80 per cent capacity during the morning, but was back to full capacity in the afternoon. Some customers reported that they could not sign in to their accounts. Westpac's online banking slowdown follows reports of ATM malfunctions at Commonwealth Bank earlier this week, and prolonged system problems at NAB late last year.