This research purpose is that how to develop new product of slim 1U Sever and more reduce to the experiment test time which keep the reliability and stability. By the dimensional analysis method, carry on solving heat dissipation way. Via my thesis is seven items of result and discussion which show as follows: Applied to 1U Server by π theorem, come out the geometric form ratio, air fluid Reynolds number and generates power on the CPU what correspond with thermal resistance；Via the curve graph (geometric form ratio- thermal resistance) is clearly show where is optimum design the thermal resistance between “saturated zone” and “unsaturated zone”on CPU power；And utilize the relation of the curve graph and “the geometric form ratio- thermal resistance” which fast determine the best thermal resistance in the 1U server products；Can be clear and fast analyzing and get to result by the curve graph.，will shorten the research and development in the experiment test time；Accuracy is improving dispel the heat and simulation by CAE of analyzing；Set up thermal simulation analysis and revision parameter database in 1U Server；The module group design what do benefit to researching and developing from many product resource； Take more different size module that still come to test real data evidence, can close ture data. We can close to survey the Flotherm difference that simulation analyzes clearly, will become the job domain that studies in the future.