Had the idea a few weeks ago to build up a small farm (as I now know it is called), but dismissed it for being ideotic to spend all that money just to get more points. Now I see there are even bigger nutters out there I'm toying with the idea again.
Or better said, can't make myself stop thinking about it even though I should be working now.
Anyways, 195 euros (1$ = E1.1) is the cheapest setup I can come up with so far. (ECS KM266 based mAtx mobo, XP 2000+). That is with a cheapo PSU and fan replaced by a papst NGL to shut it up. You can cut down on the costs by running 2 or 3 units on one 400W PSU (and get a really silent one), but you'd have to find a place to get mobo power connectors (or find another way to connect the power).
It would be great building a (closed) rack with 5 or 10 of these AND make it as silent as possible, for the fun of it. And with minimum costs that is... 10xSLK-800 + 10xNexus PSU adds too much to the costs. For example make one central duct, connected to all cpu (passive) heatsinks, and with one big outtake on the top of the cabinet with one or 2 silent 120mm fans. Would it work?
Dunno if I'll ever build this, but it's fun to hypothesize.
Oh, and you don't have to buy 10 units all at once ($2000+
), can also buy them one at a time when you can spare the money.