Seti computational farm

If this dosn't get posted here moderators please let me know where it goes...

I have two machines running seti@home, my main computers, a windows quad core and a linux dual core machine.

I am thinking about making some kinda crazy construction with old computers just for seti@home...

Can anyone who has done a bunch of machines let me know about their experiences?

Have a big empty cellar, would like to do 10 or 20 (or 50) machines running seti@home.

Please let me know of anyone's experiences doing so...
I am interested in how much the electric bill goes up per machine...
I am also interested in any stories, experiences, or wisdom on doing
something like this from those who have done so...

Steven

What do you pay for electricity?
____________

If you run 24/7 figure $150.00 per machine + or - $50.00.

(from someone who has done this) ... Your better bet, on a WU per watt ratio is to invest in a modern multi core machine , stuff it with economically priced gpus and let it rock.
I ran as many as 12 old machines at once for several months and my best rac was 2500 and I was consuming 22kwh a day

My newish I7 860 and two gtx 460 gpu pulls a solid 20,000 all by itself. It draws a hearty but much more economical 8 kwh

Yes perhaps from an electric standpoint I'd be better off with quad core machines and just forget the pile of old pcs I have sitting around collecting dust. Most of those machines are 1ghz-2ghz single core machines.

I'm a bit confused by the gpu thing. If I understand correctly, does this mean I can just plug a bunch of extra video cards with fast gpus into each machine I plan to use for seti@home/boinc? How many video cards can I jam into each machine?

How many video cards can I jam into each machine?

Thanks for your thoughts guys. I think I will just add one more modern machine to my current setup. Something like a quad core with 4 or 5 gpus I think would be best way to increase my output alot, without my power bill skyrocketing.

I have very little experience with gpu computing. If I got a quad core machine with say a good nvidia gpu card that is pci-express for main video...

What do I do about the gpu cards? say the machine has 4 pci slots... Can I just get 4 pci gpu cards, plug them in and be good to go?

That would be kinda cool, a quad core machine with 5 gpus means 9 processors cranking away on projects... I think that could increase my output alot.

Any thoughts or advice on this I would greatly appreciate. I think I'll be doing
an ebay fundraiser, selling off spare parts in order to pay for this new box.

Thanks for everyones thoughts, advice and knowledge on this...

Steven

"It has a 30K RAC"

I'm not familar with this term or ratings, is that a measure of computational
ability?

How can I find this info on my current machines or measure?

Oh I get it, recent average credit... mine shows a whopping 81...

Not sure why that shows as so low, but I did just get started again.

I just started up boinc on these two machines again recently....

If you have just restarted SETI then your RAC will need time to build that back up again (anything up to 8wks or so) but now compare your Quad against mine (I take it that yours is a Q6600 too), Computer 5712423, (though with the recent server problems its RAC is about 2K down), and you'll likely realise that a better GPU or 2 will help you along by a large margin. ;)

Cheers.
____________

GenuineIntel
Intel(R) Core(TM)2 Quad CPU @ 2.40GHz [Family 6 Model 15 Stepping 7]
(4 processors) NVIDIA GeForce 8600 GT (241MB) driver: 258.96

There is my main computer... Maybe I should just add gpu cards to this and my
dual core linux box?

Steven

Maybe you should figure out why you are
producing so many errors first.

Ahh, I see you're getting some help in
another thread. Ignore above.

Perhaps you should start with one newer/more
powerful GPU card and some experience with
the problems that entails. Then you could
move on to building a super cruncher.

If you want serious crunching power, GPU is the only way to go. The CPU is not that important. Things to have in mind are power consumption, heat management and GPU spacing.

Power
Choose the GPU that gives you the most FLOPS for your budget, and check what it will cost on the electricity bill. You can check this comparison for those numbers.

You have to have a power supply that can supply all the power the GPU(s) need, plus about 150 watts for the rest of the computer. But remember that running a power supply at close to 100% capacity is a sure way to get a short life span, get a much larger power supply than what you need.

Heat
Heat kills eletronics. High end GPU:s often move the heated cooling air outside the computer chassi, others just whisks the air around while passively cooled GPU:s doesn't move the heat away at all. Plan the airflow in the box, use extra fans if necessary. Get a temperature monitoring program, like GPU-Z, to make sure you don't overheat.

Spacing
High end GPU:s often require dual slots. Check the motherboard slot spacing what fits your motherboard. Also, single slot spacing might not be beneficial to airflow.

Allright I think I understand more but I'm still asking, do I just get pci gpu cards and can load them up in one machine, say 4?

Knowing how I do things, I'll get the computer first make sure it has a very large power supply, I can add some extra fans for cooling, then add gpus every so
often until all slots are filled?

Steven

I kinda meant add gpus as my extra hobby funds allow... I don't think I can afford to buy another machine and 4 gpu cards all at once, but I can get a machine, wait a bit, buy a gpu card, wait a bit, and so on...

Thanks for everyones advice, would love to have a powerful system to increase my output for the project.

Best regards,

Steven