The previous system was a Sun Microsystems Inc. E10,000, which was costing upwards of A$800,000 (US$611,000) in maintenance fees for the hardware alone.

"Comparing the transaction throughput wasn't a fair comparison as the E10,000 was older, but what was important was we could do the port, it was stable, and not expensive," Spencer said. "And the Sun Solaris competencies could be migrated across."

With the data warehousing projects now merged, the NAB has 10, 4-way Itanium-based servers in a shared grid infrastructure.

Spencer said moving from a "big SMP" system to low-cost hardware was a big change for the bank, but it has resulted in faster processing and more flexible procurement.

"Capacity planning for a new project is inherently risky, [but] we can buy additional capacity in lots of A$40,000 which is easy to 'smooth out' to the business," he said.