Do your research before building an HP z230 workstation, especially from eBay parts!
I don't like the narrow fan/cooler spec HP uses on some models as others (like the Pavilion) are square and not 'narrow rectangular', regardless of what is more correct in real world use. I do like that it uses Cooler Master by default. I couldn't have made a better decision myself.
Wins: Cooler Master fan, a known successful brand name in cpu and case fan cooling.
Losses: Finding a 'narrow' style backplate for the cooler for install in a non-Z230 case. Guess I will sell the brand new Corsair!
Lesson learned, if one is going to rebuild a workstation, use it's original case, even if you have to drill two holes to install a power supply over 400 watts, which is what I am planning to do on this build.
I found these guys helpful regarding the product and making this work. I recommend reading and watching this blog.
greenpcgamers DOT com search for z230 in their blog.