might help to know german ... I don't ... and with the GTX 770, you need a computer ... and ... with that we are far from the very old Beowulf cluster concept ...
I finished physics in 1989 (27 years ago) and I was dreaming of building one at the time ... forgot about that and now ... finding it again !
It is a question of :
1- harnessing the compute power of my 7 systems lying around my house (a project in itself, 4 raspberry pi 2, all running some variations of linux, 2 of them security systems hook to doors and Pir sensors, 2 others for research (fun), 2 tower linux systems, one for dev, one for my cnc, and last, my portable pc, all that on my Gb network), and
2- building a Beowulf cluster with cheaper systems available now ...Now, imagine a Beowulf system built with super nodes ... like the TX1 (thanks for your GPU heads up) ... at around 2 to 3K ... concentrate your suggestions in that direction please ... and be happy ! At 53, bitching mode is off ... I do appreciate concerns about things though but I like to be positive ...
I talked about the TX1 because I found it ... and I liked it ... it was another possibility 
and it fared better than the TK1 ...
TX1 has 256 cores the TK1 has 192 ... ok that is close ...
TX1 has 4 Gb ram the TK1 has 2 ... ok that is not close ...
TX1 is cortex-A57 but TK1 is Cortex-A15 ... and
TX1 is MPCore, I have no idea about the TK1 ...
and TX1 comes pre loaded with linux ... that is a plus for me
I looked at Anaconda and ... wow !
I'll add a 64Gb SD card (or microSD depends on what I buy) to all of them, to have more dead memory close by each processor. The cluster will also have a 3Tb private cloud hard disk (I have not selected it yet ... I do have one at home and every computer is mounting it all right)
On the fun part, have you looked at BlueDBM from MIT ? You got to love that