Quote from: coinpharmer on March 11, 2014, 08:00:22 PM

thanks for this detailed post.

for me, space is not a issue, I would be willing to give a 10x10 bedroom to the project, if a rig so large can be build with 10 btc.

cooling is not a problem, I have 2 large duct fans that each move 720 cubic feet of air per minute, and one smaller fan that moves 300 cubic feet per minute, that would be able to easily exchange the rooms air. I have 220 wired up to the outlets of this room so big appliances can be easily ran. I had hoped to get a neptune in there but I was not able to get funds lined up in time...

You're welcome. To address what you said -- 220v is not going to help you with GPUs, and would not matter for ASICs. Each set of 10 ASICs as they are currently sold, running in lower power mode use 70 watts approx, plus accessories such as USB hub, router, or rpi. Assuming money wasn't an issue, you could run approx 25 sets of ten, or 250 units on a single 120v/15a bedroom circuit. Heat generation with at least 40 units is negligible as long as the room has decent airflow.

For reference I have 2 of my rigs (10 R9 280x) running in a 10x10 utility room, with an outside window. It can warm the room from 70-80 in less than 10 minutes with the cooling turned off. I have a fan in the window blowing outside air in 24x7 -- from 20*F to 70*F outside air. When it's 50*F and over, it's insufficient to keep the room below 80*F. At 80*F, my cards are pushing 80*Celsius, at which point I have them set to clock back to cool off. So, I have to keep the AC running in that room all day to offset the heat gain.

Although, as people are starting to discover now that the unseasonable cold, long winter is coming to a close in the US, that airflow is by itself, not enough. GPUs generate such heat that it's not enough to simply move the hot air around, you need *something* to pull it out of the house entirely. It's 50*F outside, and I'm running A/C units to keep the temp under control indoors. With Gridseeds, it's like running light bulbs. Not so hot if you have 1 or 2 (sets of 10), but 5-10 start to warm the room a little bit. This will be so much worse in the summer when instead of people's houses releasing heat all day, they are getting warmed up constantly.

The size requirements may not seem like much now, but when in a year people are hashing ten times faster with devices that use up 90% less space, you will be left with a lot of wasted space. The alt coin market in general is looking depressed. Gridseeds are still shipping and coming online like mad. I believe there will be a bit of a market shock in a month or so, when everyone's preorders come in and users get their bugs worked out. A lot of capacity is going to come on line, driving profits even lower, then the demand will fall out of the bottom of the ASICs when ROI is looking more like 10-12 months, if ever. When that happens, prices will adjust lower on them, and it will be a better time to get in. Just one miner's opinion. Wink