Originally Posted by Kirby54925
$10k? Geez, you guys must be rich or something. I had to save up for nearly a year just to get my GTX 570 and the Megahalems.
i was keen to work out exactly how much it would cost to put out a RAC that would earn a top 10 rac positon, and to get into the top 10 on RAC, you need to BOINC ~5M ppd, and that can actually be achieved for under $10K
Of all the GPUs around, I'm a BIG fan of the 5850. It is cheap and is capable of decent ppd. Each 5850 is capable of 260K ppd and each 5850 only costs ~$210 AUD. And compared to a 6970, it'll actually put out more ppd per watt of power used
So how many 5850's are needed:
5M ppd needed / 260K ppd per 5850 = 19.23 5850's needed
To make things easier to calculate, I'll use 20, which is capable of 5.2M ppd and will slot you into 9th position based on RAC (if run 24/7)
Now the cheapest option in the long run is to find a mobo that has 4x dual spaced pcie slots and buy 5 of them - this is because you actually save money on the extras, namely the PSU.
The cheapest mobo I know of that has 4x double spaced pcie slots is the MSI 790FX-GD70 @ $165.
And a cheap rig based on 4x 5850's and the MSI 790FX-GD70 would be something like this:
MSI 790FX-GD70 = $165
ASUS DirectCU 5850 x 4 = $828
AMD Phenom II X2 545 = $76 (quadcore unlock most likely)
CoolerMaster Silent Pro Gold 1000W = $230 (has 8x 6pin for quad gpu)
Corsair XMS3 2x2GB DDR3 1600 kit = $50
Western Digital 160GB HD = $36
LiteOn CD/DVD burner = $17
Sunbeam Techstation = $80
Total cost per rig = $1482
So each rig will cost you ~ $1482, and with each rig running 4x 5850's, each rig will be capable of ~1M ppd - to get to the 5M ppd, you'll need 5x rigs, so $1482 x 5 = $7,410
And what does that $7,410 investment get you:
9th positon in the world based on RAC (if on 24/7)
~1.9T points per year
A top 500 spot based on credit in less than 19 days
A top 100 spot based on credit in less than 67 days
A top 5 spot based on credit in ~1 year (~322 days)
A top 3 spot based on credit in ~13 months (~391 days)
As for top spot, you wouldn't get it as the top user "Steve*" is contributing almost 10M ppd - and to catch him, you have to run at least 10x the above rigs, and that'd cost you ~$15K!
Lastly, the thing a lot of ppl forget is power consumption. Each rig would consume ~900w of power per hour, so 4.5kW/h for all 5 rigs. Per day, that's 4.5kW x 24h = 108kW of power per day (24h).
Now if power costs 10c per 1kWh, you'd be paying $0.10 x 108kW = $10.80. So $10.80 per day to power all 5 rigs. That's ~$75 per week, ~$328 per month and ~$4K per year to power the 5 rigs