The Ultima-90 is not the best air cooler we have tested. That distinction still belongs to big brother Thermalright Ultra-120 eXtreme. Where the Ultima-90 carries our CPU to a stable 3.90 GHz, the eXtreme pushes it to 3.94 GHz. The eXtreme also manages a few degrees better cooling than the Ultima-90 at higher overclocks. However, in all other respects the performance of both coolers is all but the same. The Ultra-120 eXtreme is bigger, heavier and costs about $65 retail, where Ultima-90 costs about $50. However, the Ultra-120 eXtreme remains the better performer. You will need to decide which attributes are most important to you. Beyond the Ultra-120 eXtreme, we do not know of an air cooler that outperforms the Ultima-90. Several other top models match its performance, but they don't outperform it.