Just buy a professional workstation from Dell or HP. It will have better airflow/cooling (less noise and a longer life) and less problems with incompatible hardware.
If anything the cooling in Dell/HP systems is subpar, they die like all of them have cancer, and they don't work with jack. There is no reason to buy a Dell/HP system unless you are buying so many hundreds of systems that if 20-30 die it's not a big deal.
The best suggestion I have is Supermicro, but whenever you build a computer, the budget comes first, and then the parts.
If you have a 500$ budget you are gonna be buying different parts than if you have a 2000$ budget.
Supermicro is your friend, though. They are the cream of the crop in the high end motherboard world. ASUS, ASROCK, MSI, Gigabyte, BIOSTAR, and EVGA are also good manufacturers.
And take a lesson from Dell's mistakes, buy a good PSU, if it's not a good brand name, it's not worth buying. There have been probably millions of Dell and HP computers that have died due to the PSU. And when PSUs blow, they normally take something else with.