Data Action uses a localized version of the Harland Financial Solutions' Phoenix System, which manages accounts, processes transactions and handles daily interest accruals. It also controls other core banking requirements such as Internet banking, loan origination, CRM and collections.

However, Phoenix software requires a scalable computing environment robust enough to handle more than one million Sybase transactions an hour.

McCulloch said benchmark performance tests between HP and Sun were similar but the cost of running a mixed environment of old and new servers wasn't feasible.

"We scrapped the plan of only buying four new servers and chose to remove HP altogether and install 10 Sun servers over a six-month period," he said adding that HP had enjoyed two contract renewals with the company previously. IBM was also invited to submit a proposal for the project.

In conjunction with the storage and server upgrade, Data Action switched operating systems from Unix to Solaris.