SystemCooling has a Swiftech MCP655 12 VDC Pump to review, and it does exactly what Swiftech says; it improves on the MCP650.  There is a pot on the pump, letting you run it at anywhere between 5 and 14 V, with a simple twist of the wrist.

“In their on going quest for the perfect PC water-cooling pump, Swiftech has recently released the MCP655 12 VDC Pump, which features several key improvements over the original MCP650. The two pumps appear nearly identical from the outside but inside the MCP655 has a new chipset controller, which allows the pump to run considerably quieter and includes a built-in potentiometer for adjusting the pump’s speed. The head and flow characteristics have slightly improved in the midrange as well and the MCP655’s compact design and quiet yet powerful motor make it ideally suited for heavy duty cooling applications where space is limited.”

Here are some more Cases & Cooling reviews from around the web:

Click Here to go to Cases & Cooling   CASES & COOLING