crunching computer(s)

Spend your money on the best graphics card(s) you can afford / will fit in the box / you have enough power supply to run.

Now I have a couple of "dumpster dived" core 2 duos. These owe me nothing, I picked them up with dead hard drives or power supplies (Can't remember exactly what, but they were easy fixes with cannibalised parts) If I had $500 to spend I'd buy a couple of $200-300 CUDA capable cards that would run on the normal 450 watt power supplies that are in them. A GTX 660 or similar maybe?

The older Core 2 is basically just there to feed the GPU, and it will have enough grunt to do that just fine. It's not going to make a super cruncher, but will give you some good bang for your buck, AND actually work as a decent game machine as well. Hard disk, Ram, network card etc don't really matter. It needs something, but as long as you have enough Ram to run Windows and a few boinc tasks (2gb?), and some sort of hard disk (enough to load windows and some work units) those things don't really matter. If the old 80gb disk curls up and dies next year, so what, nothing important is lost.

Now if you have more $$, then a new board, with multiple PCI-E slots, and a seriously grunty power supply, and 2 or 3 top end cards are a good option.

But if you are putzing about on a budget, play with some older machines and 1/2 decent CUDA cards.

Ian

Every few months Tom's Hardware does a $500 PC. Not something you should follow religiously but a handy cheat-sheet nonetheless. What they do is try to get the best GPUs into systems that are balanced enough to feed them. That's pretty much the goal for any Seti crunchin' PC too.

Last one was in August. New one could be out soon:

http://www.tomshardware.com/reviews/gaming-pc-overclocking-pc-building,3273.html

Hope it helps.

Yes, that's a good write up on how to build a value for $$ PC that still has decent performance. You can see how the biggest budget item is the GPU, as that has the most effect on performance (for gaming and SETI work anyway)

Money spent building something like that isn't wasted as it's a "current" spec PC. Friends or family can use it as a games machine or any other PC use if needed.

Sure it's easy enough to say, I'l just get a better CPU, or a system board with 2 PCI-E slots, or more ram, or...

But then it's not a $500 PC any more, and it's pretty easy to make it a $1,000 PC

Ian

i am running an 8 core cpu now, but if i were to do it again.
first I would set aside at least so of the build money so that I could,
pick up parts that were on sale. I would get an a10 5800k apu and the fm2 motherboard that it takes. The a1 5800k is a 4 cpu core processor with a 7000 series gpu on chip. this gpu will not rock the world but it can do a nice amount of crunching and you need no video card to start. The fm2 motherboards are cheap $50 to $90 and even the $50 boards can be found with 2 pci express slots.
So $138 for apu $50 for motherboard,the apu natively supports pc 1866 memory.
for $180 for apu and board plus mem power supply and case you are gpu crunching with 2 open e-pci slots more gpu's later. good luck with your build whatever you decide to build and let us here about it.
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For crunching, allways remember the #1 rule:

Buy the best GPU you can!
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