MSI mainboards never fails in delivering an impressive package with lots of goodies within. It has the best features like D-bracket, 1Mhz stepping for your overclocking needs. We were able to increase the FSB to 112Mhz CAS2 Ultra, voltage:1.85v memory running at 298Mhz scoring 1239/1248 in SiSoft Sandra memory benchmarks. Voltage tweaking is also available if you find that the current performance is not enough for you. Documentation is also pretty well written and BIOS screen shots and explanations of the various BIOS settings are direct to the point. The BIOS needs a bit more tuning to make it better at DDR333. Overall, a well packaged P4 DDR solution.
FULL STORY @ OCWORKBENCH (http://www.ocworkbench.com/hardware/microstar/645ultra/645ultrap1.htm)