We reported earlier that the folks over at XtremeSystems took advantage of the fact that the new Mac mini's CPU is socketed and performed a dramatic upgrade on the unit by swapping out its 1.5GHz Core Solo for a 2.16GHz Core Duo. As MacRumors reports, the same folks have taken things a big step forward by swapping out the mini's CPU for a pre-release version of the upcoming Intel Merom processor. That's right - a simple CPU swap with no other reconfiguration was all it took.

The Merom, a laptop processor, is one of the first implementations of the new Intel Core Microarchitecture (previously known as the Intel Next Generation Microarchitecture) which is a ground up design that replaces the aging NetBurst and Pentium M microarchitectures. A dual core 64-bit processor built on a 65nm process, the Merom features a relatively short 14-stage pipeline, 4MB L2 cache, and virtualization technology. The Merom provides 20% more performance at the same power level as compared to a similarly clocked Core Duo.

Previous performance demonstrations by Intel:

The Merom is expected to be released in late 2006, along with its siblings, the Conroe desktop CPU and the Woodcrest server CPU. Doubtless the Conroe will sit at the heart of the upcoming Intel-based Power Macs while, down the road, the Merom will replace the Core Duo as the MacBook Pro's processor.

This upgrade should also work fine on the Intel-based iMac, which has a socketed CPU like the mini. The MacBook Pro's CPU is suface mounted, unable to be swapped out. For owners of Intel-based Macs with socketed CPUs, quite an upgrade path has been revealed, one most did not anticipate.