I'm running WRF weather model. That's a ram intensive, highly parallel application.

I need to build a HPC cluster for that. I use 10GB infiniband interconnect.

WRF doesn't depends of core count, but on memory bandwidth. That's why a core i7 3820 or 3930K performs better than high-grade xeons E5-2600 or E7

Seems like universities uses xeon E5-2670 for WRF. It costs about $1500. Spec2006 fp_rates WRF bench shows $580 i7 3930K performs the same with 1600MHz RAM.

What's interesting is that i7 can handle up to 2400MHz ram, doing a great performance increase for WRF. Then it really outperforms the xeon. Power comsumption is a bit higher, but still less than 20€ a year. Even including additional part I'll need (PSU, infiniband, case), the i7 way is still 700 €/cpu cheaper than Xeon.

So, is it ok to use "gamer" hardware in a HPC cluster ? or should I do it pro with xeon ?

(This is not a critical application. I can handle downtime. I think I don't need ECC?)