Let's say we want to build a supercomputer with the same computational throughput as GPUGRID.

How much would it cost to build?
How much would it cost to keep it running? (electricity bills, etc)

Let's say we base our calculations on a throughput of 400,000 GFlops (400 PFLOPs).
And electricity costs are $0.10 for 1 KWh.

Go ahead! (please motivate your answer)


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Here's my calculation:
A GTX570 gives a theoretical output of 1400 GFLOPs
400,000/1400 = ~285 GTX570 required!

285/3 = 95 Motherbords, CPUs, Memorysticks, PSUs(3 GPUs on each motherbord)

95x Mid-segment Motherboards (95 x USD 150 )
95x Quad core CPUs (95 x USD 150 )
95x 4GB DDR3 mem (95 x USD 30 )
95x 1000W PSU (95 x USD 100 )
285x GTX570 (285 x USD 250 )
Gives a whopping total of USD 112,100 (not taking into account the costs to house and cool all this hardware)

The running costs for this beast:
700W for each system gives a total of 66,500W
66,500 x 1.5 (due to cooling and efficiency losses) = ~100KW

24 hours: 100KW x 24 x USD 0.10 = USD 240
a week: 240 * 7 = USD 1,680
a month: 240 * 30 = USD 7,200
a year: 240 * 365 = USD 87,600 (almost the costs of buying the hardware!!!!!)

Let's say we base our calculations on a throughput of 400,000 GFlops (400 PFLOPs).

And with the power in this hour (serverstats) we are powering an supercomputer that would fit into a great Place 37 on the Top 500 List of Supercomputers :)
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DSKAG Austria Research Team: http://www.research.dskag.at

4x690 in 18 computers would be half the electricity cost. 400W power use per 690 card (measured), 200W for CPU and SSD, so 1800W per computer, divided by XFX 850+850+550 PSUs or a hugely expensive but more compact one (I say XFX because they have all the wattage on just one rail, and is guaranteed to give the said amount of power, so they're very easy to interconnect).

18x XFX 550w 100 USD
36x XFX 850W 140 USD
18x Corsair 2133MHz 2x4GB 80 USD
18x Corsair SSD 120gb 100 USD
18x ASUS Maximus V Extreme 500 USD
18x Intel i7-2700K 500 USD
72x gtx 690 72000 USD
100 000 USD put together.

If however these were placed in cold places, they could use the computers as the main source of heat (homes, offices, garages etc), and thus cost practically nothing to run.