First of all let's speak about the choice of graphic cards. Nvidia cards are definitely the one to choose from. Cuda – the language – in which some portions of Micromagnum is written, is available only on Nvidia cards.

This narrows the choice down to another big choice:

The differences are many (some quite small):

Now to the more hardware centric part:

We don't trust the consumer fans on the graphiccards. We don't think that these fans are build with 365/24 usage in mind. So if you choose to use Geforce cards have in mind to buy an extend card for simple swapping in case of an error (or maybe have a spare fan).

Active coolers are suboptimal for building a dens-packed Cluster:

But... you definitely will save a lot of money – if power-consumption is of no concern for you – you may go quite well with these cards.

The market for Nvidia-cards is ever swapping – so the "very best" card is hard to choose from – remember: large memory is a must-have for these type of calculations – the bigger the better.

For installation/software, we do use simple Ubuntu-Linux with the newest nvidia-drivers – and they do work quite nice.

If you have further question please feel free to ask them !